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>> [Daqq tal-mużika]

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>> DAVID J. Malan: So I biss
riedu li tikkalma lill.

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Nixtieq eku eżattament dak Scaz
qal dwar memorja istituzzjonali.

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CS50 kien madwar għal
xi 20 snin fil-Harvard.

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U r-realtà hija, minn
l-anzjani fuq l,

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kull sena hemm riassigurazzjoni
li l-freshmen, il sophomores,

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u l-Juniors u
wkoll l-anzjani jieħdu

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CS50, li inti tispiċċa tagħmel multa.

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>> Ir-realtà hija, l-istudenti
ma jonqsu CS50.

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Fil-fatt, fil-każijiet rari
fejn aħna kellna Es jew Fs,

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huwa verament kien minħabba
ċirkostanzi estenwanti,

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jekk huwa medika jew personali.

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Ds huma oerhört komuni kif ukoll.

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U nista 'ngħid komdu, għalkemm aħna
tipikament ma jiżvelawx istatistika,

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iżda minħabba li m'hemmx
tradizzjoni istituzzjonali hawn tkun xi tkun,

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maġġoranza ta 'studenti fil CS50
tispiċċa jkollna gradi firxa.

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A blokki sinifikanti jispiċċaw
jispiċċaw fil-medda B wisq.

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>> Għalhekk anki jekk inti tista 'tkun
jsarraf f'għadd ta 'tlieta moħħok

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60% u għalhekk
Ds, jew Cs, jew simili,

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huwa verament ma line
mal-realtà.

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Fil-fatt, aħna tfisser eżattament dak li aħna
jgħidu fil-bidu tat-terminu

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li tant studenti fil CS50, kemm
fil Cambridge u hawn fi New Haven,

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qatt ma ħa kors CS qabel.

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U dak tabilħaqq finalment jgħodd
huwa fejn inti tispiċċa fil-ġimgħa 12

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relattiv għall ruħek fil żero ġimgħa.

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Issa għandna multipli
binarji fil-kors

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kif inti know-- inqas komdu, aktar
komdu, x'imkien bejniethom.

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U fil-fatt, meta ikollok
istatistika dwar kwizz din il-ġimgħa,

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taqtax qalbek jekk, speċjalment jekk
inti tħoss li int madwar il-medja

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jew taħt il-medja jew il-medjan,
speċjalment peress li aħna ma neċessarjament

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jieħdu dawk demografija kollha
kont ta 'nofs it-semestru

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l-istatistika gradazzjoni.

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>> Fi kliem ieħor, nafu
statistikament kull sena

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li l-istudenti li huma inqas komdi,
do ftit agħar fuq il-kwizz.

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U l-istudenti li huma aktar komdi
do ftit aħjar fuq il-kwizz.

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Iżda kull li jippromettu fis-sillabu
u wkoll fl-ewwel ġimgħa ta 'lectures,

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nieħdu kollha ta 'dak in kunsiderazzjoni.

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>> Tabilħaqq, fl sena għan,
dak li aħna jispiċċaw jagħmlu

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huwa normalizing punteġġi kollha madwar
sezzjonijiet, kemm fil Cambridge

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u issa hawn fi New Haven,
li jfisser filwaqt li jitqiesu

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l-istili differenti, l diverġenti
harshness, il tip differenti

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ta 'personalitajiet li l-individwu
TAs hawn u fil Cambridge

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sabiex int mhux fuq
żvantaġġ anki jekk inti biss

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jiġri li kellhom TF jew AT
li kien ftit iktar iebsa fuqek

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fil moħħok.

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>> Tnejn, nieħdu in kunsiderazzjoni l-kumdità
livell u l-isfond attwali, jew nuqqas

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tiegħu, meta tieħu
punteġġi kwizz l-ispettaturi.

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Allura dawn iż-żewġ elementi li.

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U fl-aħħar tal-ġurnata,
għaliex dan huwa dejjem il-każ

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li student spiċċaw
f'sezzjoni inqas comfy

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meta hu jew hi verament kienet ikkontrollata
fi fin-nofs jew viċi versa,

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kollox huwa tant
oerhört individwalizzat.

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Tabilħaqq, inti se tikseb imdejqa lejn magħna fil
l-aħħar tat-terminu meta ninsabu tard

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sottomissjoni gradi tiegħek minħabba li bl
Scaz, u Jason, u Andy, u I,

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u t-tim se għamlu
fil Cambridge huwa litteralment

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mijiet ta 'emails lura u
raba kollha mijiet tal-korsijiet

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TAs, hawn u fil
Cambridge, talbithom liema

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jaħsbu ta 'dak kollu istudenti tagħhom
ibbażata fuq abbozz tal-gradi.

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U kollox hemm wara
huwa oerhört individwalizzat.

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Dan safejn irridu jsiru jafu lilek
f'sigħat uffiċċju, sezzjonijiet, u aktar,

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kollha ta 'dak wisq tittieħed in kunsiderazzjoni.

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>> Allura jekk aħna tendenza li jużaw dan ħamsa
punt iskala, jekk jogħġbok, aqla yourself

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mis-suppożizzjoni li
tliet huwa tabilħaqq 60%.

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Huwa maħsub li jkun tajjeb.

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U l-assistenti tagħlim
huma ċċarġjati fil-bidu terminu

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biex jippruvaw iżommu punteġġi
fil-twos, u threes,

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u fours jvarjaw sabiex inkunu
attwalment ikollhom kamra li jikbru.

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U aħna attwalment
paragun ta 'kejl li permezz tiegħu

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nistgħu nagħtuk utli
feedback dwar kif qed tagħmel

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u kif int miexi.

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Allura jekk jogħġbok jieħdu dik il-qalb.

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>> Hemm xi mistoqsijiet I jistgħu jgħinu
jindirizzaw jew tħassib I jistgħu jgħinu tikkalma?

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Jew wegħdiet I tista 'tipprova li żżomm?

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Nru?

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KOLLOX SEW.

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>> Kull dritt.

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Allura ma 'dak imsemmi, dan huwa CS50.

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Dan huwa l-bidu tal-ġimgħa
sitta hawn fi New Haven.

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Ejja tibda bil qasira
jbaxxu tad-dwal

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li tiffissa l-istadju għall-kontenut tal-lum.

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[Daqq video]

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[Daqq tal-mużika]

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-He Daħal ma 'messaġġ.

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Bil-protokoll kollu tiegħu stess.

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Huwa daħal għal dinja ta 'firewalls jibred,
routers uncaring, u l-perikli ferm agħar

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li l-mewt.

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Hu mgħaġġel, hu b'saħħtu, hu TCP / IP.

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U hu ltqajna l-indirizz tiegħek.

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Ġellieda tax-xibka.

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>> [END Daqq]

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DAVID J. Malan: Kull dritt.

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Dan huwa CS50.

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Dan huwa l-bidu ta 'sitt ġimgħat.

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U dan huwa l-bidu ta 'ħarsa tagħna
fil-internet u l-web programmazzjoni.

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U, forsi aktar excitingly,
illum jimmarka t-tranżizzjoni għalina

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mil-linja ta 'kmand tagħna
dinja ta 'C għall-web

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dinja bbażata tat PHP, u HTML,
u CSS, u SQL, u JavaScript,

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u għalhekk ħafna aktar li huwa fuq l-orizzont.

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>> Iżda l-ewwel, dan wasal għall-attenzjoni tagħna
fil-mixi madwar il-kampus li hemm

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huwa tal-banju ċerta hawn fi New
Haven imsejjaħ il-kamra Harvard, li

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huwa ftit greyed hawn.

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Iżda fil-fatt, xi ħadd marru għall-ħin
u spejjeż ta 'inċiżjoni fil-kamra Harvard

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fuq dan hawn kamra.

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Grazzi għal dan.

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Ma nistax ngħid għandna
analogu fl Cambridge għadhom,

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iżda naħseb għandna proġett ftit
għalina issa meta immorru lura.

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Allura nirringrazzjak għal dak.

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>> Allura a quick ħarsa lura lejn
fejn aħna jitħalla 'off aħħar ġimgħa

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u fejn inti qed tmur din ġejjin
ġimgħa bi problemi stabbiliti ħamsa.

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Għalhekk fl problema sett ħamsa, inti ser tkun
isfida li timplimenta spellchecker.

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U biex tagħmel dan, inti ser tkun
mogħtija test pretty big

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fajl ma simili 140.000 kliem Ingliż.

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U tkun taf tkun ikkontestata tiddeċiedi
fuq struttura tad-data li magħhom inti

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tixtieq li tagħbija kollha dawn il-kliem
fil-memorja, u fis RAM,

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u mbagħad jimplimentaw ftit funzjonijiet,
waħda minnhom se tkun jiċċekkjaw.

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Li bih meta għadda argument,
kelma, check funzjoni tiegħek

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sempliċiment se jkollhom
ngħid vera jew falza,

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din hija kelma fid-dizzjunarju.

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>> Imma int ser ikollhom xi
diskrezzjoni disinn u l-isfidi

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meta niġu għall-implimentazzjoni ta 'dak.

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Fl-implimentazzjoni aktar sempliċi,
inti tista 'ċertament

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timplimenta spellchecker fil
-dizzjunarju sottostanti

127
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ma 'dak it-tip ta' struttura data?

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Inti biss bżonn li taħżen kollu kemm hu
mazz ta 'spag fil-memorja?

129
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X'hemm il-go biex twieġeb
minn ġimgħatejn forsi?

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UDJENZA: Array.

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DAVID J. Malan: Tista 'tuża l-firxa.

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U li mhux kollha li ħżiena.

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Imma inti ma neċessarjament jaf
qabel kemm hu kbir ta 'firxa

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int ser bżonn, jekk inti ma
jafu l-proċess ikun hemm bil-quddiem.

135
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Allura int ser ikollhom
jużaw ftit ta 'trickery

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bħall malloc, bħal aħna bdew jużaw.

137
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Jew nistgħu jindirizza
li jikkonċernaw bl-użu

138
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liema struttura oħra data li l-
Kien tip ta 'titjib marġinali

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fuq firxa?

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UDJENZA: Lista Marbuta.

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DAVID J. Malan: Bħal marbuta
lista, fejn irridu jiksbu xi dinamiżmu.

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Iżda hemm ftit spejjeż aktar.

143
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Għandna pointers li jżommu.

144
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U inti stajt għadhom mhux kodifikati dan
up, iżda hemm definittivament

145
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li jkun ftit kumplessità aktar
milli sempliċement jużaw parentesi kwadri

146
00:06:28,473 --> 00:06:30,080
u jaqbeż madwar firxa.

147
00:06:30,080 --> 00:06:33,340
>> Iżda running time ta 'firxa,
jekk int tiftix għal kelma,

148
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jista 'log tal n.

149
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Iżda għal darb'oħra, jista 'jkun
ftit mhux trivjali

150
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biex jibnu li firxa mhux
jafu l-daqs minn qabel.

151
00:06:38,734 --> 00:06:41,150
Lista marbuta għalkemm, jekk inti
biss jaħżnu mazz ta 'spag

152
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f'lista marbuta,
x'hemm rbit għoli tiegħek

153
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fuq tmexxija ħin se tkun ta 'tiftix
għal jew jiċċekkjaw kelma f'dik il-lista?

154
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>> UDJENZA: n.

155
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>> DAVID J. Malan: Yeah, O kbir ta 'n jew
lineari minħabba fl-agħar każ,

156
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il-kelma huwa bħal kelma Z
it-triq kollha fl-aħħar.

157
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U minħabba ta 'lista marbuta,
minħabba li dawk vleġeġ fil-kontumaċja,

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f'lista marbut waħdu, mur biss
minn direzzjoni waħda għall-oħra,

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inti ma tistax jaqbżu madwar.

160
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Int għandek issegwi kull wieħed minnhom.

161
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>> Allura aħna propost fl-aħħar tal-ġimgħa li għaddiet,
ħamsa ġimgħa, li hemm modi aħjar.

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00:07:05,505 --> 00:07:08,727
U fil-fatt, il-Grail qaddis
jkunx verament ħin kostanti

163
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li biha meta inti tixtieq
li wieħed ifittex kelma, inti

164
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tikseb risposta immedjata irrispettivament
ta 'kemm kliem huma diġà

165
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fil-dizzjunarju tiegħek.

166
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>> Dan huwa konsenja 'l-artist ta'
dak li inti tista 'sejħa tabella hash.

167
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U tabella hash huwa tip ta 'sbieħ
amalgama ta 'array-- mfassla vertikalment

168
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hawn, biss because-- u mbagħad
marbuta list-- tiġbed orizzontalment hawn.

169
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U t-tabella hash jista 'jkun
implimentata għenieqed ta 'modi.

170
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Dan silta minn textbook jiġri
tuża dati tat-twelid dawn in-nies

171
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bħala l-mezz li bih huwa deċiż
fejn jitqiegħdu l-isem ta 'xi ħadd.

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Allura dan huwa dizzjunarju
jekk inti se 'ismijiet.

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U sabiex jitħaffef it-tqegħid
ismijiet fis din l-istruttura tad-data,

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li tħares lejn, apparentement, tat Dawn in-nies
twelid dati fir-rigward ta 'xahar.

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>> Allura huwa 1 sal-31.

176
00:07:50,570 --> 00:07:52,910
U tinsa dwar Frar
u każijiet kantuniera bħal dik.

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U jekk birthday tiegħek huwa fuq Jannar
1, jew fi Frar 1, jew 1 Diċembru,

178
00:07:57,050 --> 00:07:59,890
int ser jispiċċaw fil
l-ewwel katina top up.

179
00:07:59,890 --> 00:08:02,150
Jekk id-data tat-twelid tiegħek huwa
bħall-25 ta 'xahar,

180
00:08:02,150 --> 00:08:04,567
int ser jispiċċaw
fuq in-numru barmil 25.

181
00:08:04,567 --> 00:08:07,400
U jekk hemm diġà xi ħadd hemmhekk
fi kwalunkwe wieħed minn dawk il-postijiet, liema

182
00:08:07,400 --> 00:08:10,470
tibda tagħmel ma 'dawn marbuta
listi hija jinħietu flimkien

183
00:08:10,470 --> 00:08:14,320
sabiex inti jista 'jkollhom arbitrarja
numru ta 'nies, jew xejn,

184
00:08:14,320 --> 00:08:15,580
f'dak il-post.

185
00:08:15,580 --> 00:08:18,400
>> Allura inti għandek tip ta 'taħlita ta'
ħin kostanti għall hashing.

186
00:08:18,400 --> 00:08:21,160
U biex hash xi ħaġa mezzi biex
tieħu bħala input bħal persuna,

187
00:08:21,160 --> 00:08:25,360
jew l-isem tiegħu jew tagħha, jew twelid tiegħu jew tagħha
data, u mbagħad jiddeċiedi fuq xi output

188
00:08:25,360 --> 00:08:29,780
ibbażata fuq li, bħal tħares lejn tagħhom
birthday u outputting wieħed permezz 31.

189
00:08:29,780 --> 00:08:31,900
>> Mela allura inti jista 'jkollok
ftit ta 'żmien lineari,

190
00:08:31,900 --> 00:08:34,429
iżda fir-realtà, u kif fil
il-każ ta 'problema stabbiliti ħames,

191
00:08:34,429 --> 00:08:36,220
aħna mhux qed tmur biex tkun
taħdem P stabbiliti ħamsa

192
00:08:36,220 --> 00:08:40,059
tant dwar asintotiku tmexxija
żmien, bħall-dewmien teoretiku

193
00:08:40,059 --> 00:08:41,809
li magħhom algoritmu jista 'jmur.

194
00:08:41,809 --> 00:08:44,330
Aħna qed tmur biex jimpurtahom
in-numru attwali ta 'sekonda

195
00:08:44,330 --> 00:08:47,350
u l-ammont attwali tal-memorja,
in-numru attwali ta 'bytes ta' memorja

196
00:08:47,350 --> 00:08:48,140
inti qed tuża.

197
00:08:48,140 --> 00:08:52,710
Allura franchement, li wieħed enormi
katina ta 'bħal miljun ruħ

198
00:08:52,710 --> 00:08:56,710
huwa pretty kkritikat bil-mod jekk int tiftix
għal isem fil-lista ta 'daqs miljun.

199
00:08:56,710 --> 00:08:59,830
>> Imma x'jiġri jekk inti jaqsmu
dik il-lista fis-31 partijiet?

200
00:08:59,830 --> 00:09:04,400
Tiftix 31/01 ta 'dak
super lista twila, fir-realtà,

201
00:09:04,400 --> 00:09:05,741
huwa ċertament se tkun iktar mgħaġġla.

202
00:09:05,741 --> 00:09:07,240
Asimptotikalment, huwa l-istess ħaġa.

203
00:09:07,240 --> 00:09:08,860
Int biss diviż
b'fattur kostanti.

204
00:09:08,860 --> 00:09:10,651
U tfakkar li aħna
tarmi dawk l-affarijiet bogħod.

205
00:09:10,651 --> 00:09:13,486
Iżda fir-realtà, li għaddej
li tkun 31 darbiet aktar mgħaġġla.

206
00:09:13,486 --> 00:09:16,110
U dan huwa dak li aħna qed tmur biex
jibdew lieva fl P stabbiliti ħamsa.

207
00:09:16,110 --> 00:09:18,750
>> Allura P stabbiliti ħamsa wkoll wisq
jipproponi li inti tqis

208
00:09:18,750 --> 00:09:21,810
ftit aktar sofistikati
istruttura tad-data tissejjaħ trie.

209
00:09:21,810 --> 00:09:24,420
U trie huwa biss
siġra bħall-istruttura data.

210
00:09:24,420 --> 00:09:26,672
Iżda minflok li
ċrieki ftit jew rettangoli

211
00:09:26,672 --> 00:09:28,380
kif inżommu tpinġija
għal punti strateġiċi, attwalment

212
00:09:28,380 --> 00:09:30,840
għandha arrays kollha għal punti strateġiċi tagħha.

213
00:09:30,840 --> 00:09:33,430
U anki jekk dan huwa
bit astratta hawn biex tħares lejn,

214
00:09:33,430 --> 00:09:35,450
Zamyla fil-mixja P sett
permezz ser jimxu miegħek

215
00:09:35,450 --> 00:09:37,580
permezz f'aktar dettall dwar dan.

216
00:09:37,580 --> 00:09:39,980
Din hija struttura tad-data
li pjuttost cleverly

217
00:09:39,980 --> 00:09:44,130
jista 'jkollhom kull node jkunu ta' firxa
daqs 26, A permezz Z jew żero

218
00:09:44,130 --> 00:09:45,320
permezz 25.

219
00:09:45,320 --> 00:09:49,260
U meta inti tixtieq li daħħal il-persuna
isem fis din l-istruttura data jew isibu

220
00:09:49,260 --> 00:09:53,990
lilu jew lilha, dak li inti tagħmel, jekk il-
isem huwa simili Maxwell, M-A-X-W-E-L-L,

221
00:09:53,990 --> 00:09:57,900
inti l-ewwel tħares lejn M. U allura inti
jaqbżu l-post korrispondenti M

222
00:09:57,900 --> 00:09:59,100
fl-ewwel array.

223
00:09:59,100 --> 00:10:02,400
Inti mbagħad jaqbżu A, l-ewwel
post fil-firxa jmiss,

224
00:10:02,400 --> 00:10:03,610
wara l-vleġeġ.

225
00:10:03,610 --> 00:10:08,300
Imbagħad X, allura W, imbagħad E, allura L, imbagħad
L, u allura forsi xi tarf speċjali

226
00:10:08,300 --> 00:10:11,850
karattru, xi sentinella
li tgħid kelma jieqaf hawn.

227
00:10:11,850 --> 00:10:14,780
>> U x'hemm sbieħ dwar this-- u
iżomm f'moħħu li l-istampa hawn,

228
00:10:14,780 --> 00:10:16,797
Avviż kif truf tal
kull firxa huma maqtugħa.

229
00:10:16,797 --> 00:10:19,630
Li jinsab biss għax dan ħaġa kieku
jkun enormi u orribbli li tħares

230
00:10:19,630 --> 00:10:20,338
fil fuq l-iskrin.

231
00:10:20,338 --> 00:10:21,820
Allura huwa excerpted.

232
00:10:21,820 --> 00:10:25,920
X'hemm sbieħ dwar dan l-approċċ huwa
li jekk hemm xi miljun isem diġà

233
00:10:25,920 --> 00:10:30,890
f'din l-istruttura tad-data, kemm passi
ma jieħdu me li daħħal Maxwell?

234
00:10:30,890 --> 00:10:36,450
M-A-X-W-E-L-L-- like seba 'ish
passi biex daħħal jew tfittex Maxwell.

235
00:10:36,450 --> 00:10:39,320
>> Ejja ngħidu hemm triljun
ismijiet f'din l-istruttura tad-data.

236
00:10:39,320 --> 00:10:41,900
Kemm passi ma jieħdu
me biex tfittex Maxwell?

237
00:10:41,900 --> 00:10:43,450
M-A-X-- xorta sebgħa.

238
00:10:43,450 --> 00:10:45,770
>> U fih tinsab il-
hekk imsejħa time kostanti.

239
00:10:45,770 --> 00:10:47,960
Jekk nassumu li l-kliem
huma ċertament tmiss

240
00:10:47,960 --> 00:10:52,150
billi 20 karattru, jew 46 karattri,
jew xi numru sħiħ raġonevolment żgħir,

241
00:10:52,150 --> 00:10:53,790
allura huwa effettivament kostanti.

242
00:10:53,790 --> 00:10:57,790
U hekk inserzjoni u tiftix
a trie huwa super fast.

243
00:10:57,790 --> 00:10:59,540
Of course, aħna qatt
tikseb xejn b'xejn.

244
00:10:59,540 --> 00:11:02,740
U anki jekk inti probabilment
ma dived fis P stabbiliti ħamsa għadhom,

245
00:11:02,740 --> 00:11:06,596
liema prezz aħna probabbilment tħallas lill
nikseb dak iż-żmien aktar effiċjenza għaqli?

246
00:11:06,596 --> 00:11:07,470
>> UDJENZA: Memorja.

247
00:11:07,470 --> 00:11:08,390
>> DAVID J. Malan: Memorja, id-dritt?

248
00:11:08,390 --> 00:11:10,240
I mean, konna ma tfasslux
l-istampa kollha hawn.

249
00:11:10,240 --> 00:11:12,823
Dan silta mill-textbook
ma mfassal kollha tal-arrays.

250
00:11:12,823 --> 00:11:16,687
Hemm ammont kbir ta 'memorja u biss
pointers nulli li ma jkunux qed jintużaw.

251
00:11:16,687 --> 00:11:17,520
Allura huwa kummerċ off.

252
00:11:17,520 --> 00:11:21,050
U dan ser jitħallew lilek P stabbiliti ħamsa
biex jiddeċiedu dwar liema mod inti tixtieq li tmur.

253
00:11:21,050 --> 00:11:24,460
>> Issa din l-idea ta 'hashing, bħala
aside, huwa attwalment super prevalenti.

254
00:11:24,460 --> 00:11:27,980
Allura biex hash mezz valur, pjuttost
sempliċement, sabiex jieħdu xi ħaġa bħala input

255
00:11:27,980 --> 00:11:29,220
u jipproduċi output.

256
00:11:29,220 --> 00:11:31,270
Allura funzjoni hash huwa biss algoritmu.

257
00:11:31,270 --> 00:11:34,990
>> U ġeneralment, skop funzjonijiet hash
fil-ħajja huwa li jieħdu xi ħaġa bħala input

258
00:11:34,990 --> 00:11:39,655
u tipproduċi numru bħala output, bħall-
numru wieħed permezz 31 jew A permezz Z,

259
00:11:39,655 --> 00:11:40,960
żero permezz 25.

260
00:11:40,960 --> 00:11:44,250
Allura hija tieħu output kumpless
u qed jiċkien l-isfel għal xi ħaġa

261
00:11:44,250 --> 00:11:46,310
li l-ftit aktar
utli u maniġġabbli.

262
00:11:46,310 --> 00:11:49,250
>> U għalhekk jirriżulta fi
funzjoni popolari ħafna

263
00:11:49,250 --> 00:11:51,160
li d-dinja tas-sigurtà
u d-dinja tal-bniedem

264
00:11:51,160 --> 00:11:53,060
kienu jużaw għal snin huwa msejjaħ SHA1.

265
00:11:53,060 --> 00:11:56,260
Din hija pjuttost fancy matematika
formula li ma essenzjalment dan.

266
00:11:56,260 --> 00:11:58,870
>> Tieħu verament kbir
blokki ta 'żerijiet u ones--

267
00:11:58,870 --> 00:12:01,530
li jista 'jkun megabyte
twil, long-- gigabyte

268
00:12:01,530 --> 00:12:05,930
u qed jiċkien l-isfel għal
biss bits ftit, ftit bits ftit,

269
00:12:05,930 --> 00:12:09,082
sabiex ikollok numru bħal
wieħed permezz 31 jew A permezz Z.

270
00:12:09,082 --> 00:12:11,540
Iżda fir-realtà, huwa ftit
akbar milli sempliċiment A permezz Z.

271
00:12:11,540 --> 00:12:16,640
>> Sfortunatament, aħna qed fil-quċċata ta 'dak li
xi ħadd playfully imsejjaħ il-SHAppening

272
00:12:16,640 --> 00:12:19,840
li permezz tagħha d-dinja waslet biex
tintemm fl probabbilment ftit xhur

273
00:12:19,840 --> 00:12:22,617
ħin minħabba riċerkaturi,
biss din il-ġimgħa passat,

274
00:12:22,617 --> 00:12:25,700
ppubblikat rapport li jmur kontra l
dak ir-riċerkaturi tas-sigurtà maħsub

275
00:12:25,700 --> 00:12:29,810
għal xi żmien, bi ftit
tonfoq madwar, dak li kien dan,

276
00:12:29,810 --> 00:12:33,420
Naħseb li kien $ 175,000--
ħafna flus,

277
00:12:33,420 --> 00:12:36,540
iżda mhux hinn mill-kapaċitajiet ta '
guys ħżiena partikolarment ħżiena,

278
00:12:36,540 --> 00:12:41,560
jew partikolarment ħażin countries-- $ 175,000
tista 'tixtri inti ħafna ta' server mikrija

279
00:12:41,560 --> 00:12:42,690
spazju fil-sħaba.

280
00:12:42,690 --> 00:12:44,619
U aħna ser terga 'lura għal
l-sħaba qabel twil.

281
00:12:44,619 --> 00:12:47,410
Iżda dan ifisser biss kiri server
spazju fuq bħal servers ta 'Microsoft,

282
00:12:47,410 --> 00:12:50,285
jew Google, jew tal-Amazon, jew il-
bħal fejn inti tista 'tħallas bil-minuta

283
00:12:50,285 --> 00:12:51,670
li jużaw il-kompjuters xi ħadd ieħor.

284
00:12:51,670 --> 00:12:54,250
>> U jirriżulta jekk inti tista 'tħallas
xi ħadd ieħor biex tissellef kompjuters tagħhom

285
00:12:54,250 --> 00:12:56,730
u kodiċi run li inti stajt bil-miktub
fuqha u l-użu pretty fancy

286
00:12:56,730 --> 00:13:01,580
matematika, inti tista essenzjalment figura
kif funzjoni hash xi ħadd huwa

287
00:13:01,580 --> 00:13:05,320
xogħol, u minħabba l-output tagħha,
reverse inġinier dak input tagħha huwa.

288
00:13:05,320 --> 00:13:08,590
U għal skopijiet tal-lum,
huwa biżżejjed li jingħad, dan huwa ħażin.

289
00:13:08,590 --> 00:13:12,540
Minħabba SHA1 u hash funzjonijiet
bhalu huma super komunement

290
00:13:12,540 --> 00:13:17,050
użati fl-applikazzjonijiet ta 'sigurtà,
Konnessjonijiet encrypted fuq il-web,

291
00:13:17,050 --> 00:13:21,890
transazzjonijiet bankarji, encryption ċellulari
għat-telefowns ċellulari tiegħek, u simili.

292
00:13:21,890 --> 00:13:24,880
U hekk kull darba li xi ħadd
isib mod biex ireġġgħu lura

293
00:13:24,880 --> 00:13:28,510
inġinier waħda minn dawn it-teknoloġiji
jew jitkisser, affarijiet ħżiena jista 'jiġri.

294
00:13:28,510 --> 00:13:30,300
>> Issa d-dinja diġà kien jaf dan.

295
00:13:30,300 --> 00:13:31,310
Dan kien prevedibbli.

296
00:13:31,310 --> 00:13:34,670
U d-dinja minn dakinhar
imċaqlaq minn SHA1 għal SHA256,

297
00:13:34,670 --> 00:13:37,320
li huwa biss mod fancy ta
jgħidu li jużaw bits akbar.

298
00:13:37,320 --> 00:13:40,570
U fil-fatt, anki CS50 stess
website upgraded aħħar sena to--

299
00:13:40,570 --> 00:13:43,290
mhux li għandna quddiemna dan kollu ħafna
theddid tipprova tikseb fuq il-PDFs

300
00:13:43,290 --> 00:13:46,520
u whatnot-- iżda website CS50 s
juża l-funzjoni hash akbar,

301
00:13:46,520 --> 00:13:47,980
li jfisser li aħna se jkunu siguri.

302
00:13:47,980 --> 00:13:50,020
Allura kollha ta 'PDFs tiegħek
se jkunu siguri, iżda mhux

303
00:13:50,020 --> 00:13:52,880
neċessarjament flus tiegħek jew xi ħaġa
partikolarment privat jew personali

304
00:13:52,880 --> 00:13:53,380
għall-użu.

305
00:13:53,380 --> 00:13:56,550
Sp check out li URL jekk youd
bħal xi dettalji addizzjonali.

306
00:13:56,550 --> 00:13:59,840
>> Allura problema sett ħamsa
tabilħaqq fuq l-orizzont.

307
00:13:59,840 --> 00:14:01,560
Wieħed Quiz hija din l-erbgħa li ġejjin.

308
00:14:01,560 --> 00:14:04,479
Imma jieħdu vantaġġ tal-kariga
siegħa, kemm tonight u ta 'għada.

309
00:14:04,479 --> 00:14:07,770
U wkoll jieħdu vantaġġ ta 'ħinijiet tal-uffiċċju,
jekk int disponibbli, dritt wara dan.

310
00:14:07,770 --> 00:14:11,550
L-istaff u jien ser twaħħal madwar u jagħmlu
aktar każwali Q & A flimkien ma tonight.

311
00:14:11,550 --> 00:14:16,610
U let me nota qawwi hawn, għal
dawk minna hawn fil Haven-- Ġodda

312
00:14:16,610 --> 00:14:19,360
dan huwa assolutament kull ta Scaz
rimarki feltru, jien ċert,

313
00:14:19,360 --> 00:14:21,140
bħal daqsxejn ta 'ġlieda għat-telgħa.

314
00:14:21,140 --> 00:14:24,627
U mill-reputazzjoni, jekk inti
ma jkunux tgħallmu diġà jew jinstema

315
00:14:24,627 --> 00:14:27,710
minn xi ħbieb fil-Harvard, taf
hawn huma xi memorja istituzzjonali ġdid.

316
00:14:27,710 --> 00:14:30,790
P sett ħamsa tip ta 'tip ta'
tendenza li jkun l-agħar fid CS50,

317
00:14:30,790 --> 00:14:32,590
jew l-aktar sfida
għal ħafna studenti.

318
00:14:32,590 --> 00:14:37,180
>> Imma dak li tfisser hija li aħna qed
kważi fil-quċċata ta 'din għoljiet.

319
00:14:37,180 --> 00:14:38,270
U I really do tfisser dan.

320
00:14:38,270 --> 00:14:40,728
Hu l-aktar sfida, iżda
huwa wkoll l-aktar ta 'sodisfazzjon

321
00:14:40,728 --> 00:14:43,560
f'dak b'differenza aktar minn darba kull oħra
xjenza tal-kompjuter introduttorja

322
00:14:43,560 --> 00:14:47,980
Naturalment fl-Istati Uniti li nafu,
l-istudenti aktar ma finitura intro

323
00:14:47,980 --> 00:14:51,400
kors li diġà implimentaw
affarijiet simili siġar, u tentattivi,

324
00:14:51,400 --> 00:14:52,880
u tabelli hash, u simili.

325
00:14:52,880 --> 00:14:54,770
>> U hekk Nittama, u
aħna nittamaw li int

326
00:14:54,770 --> 00:14:57,280
ikollhom sens enormi
ta 'sodisfazzjon anki

327
00:14:57,280 --> 00:15:00,760
jekk il ġimgħa jew tnejn li permezz tagħhom
ikollok dak sodisfazzjon

328
00:15:00,760 --> 00:15:02,490
ma tħoss xi ftit bħal dan.

329
00:15:02,490 --> 00:15:05,250
Iżda let me jserraħ ras, aħna
biss erba 'settijiet P xellug.

330
00:15:05,250 --> 00:15:07,380
Allura tip ta 'dik quċċata hija fil-vista.

331
00:15:07,380 --> 00:15:12,370
>> Min-naħa l-oħra ta 'dan, fiduċja magħna,
huwa biss rolling għoljiet u sħab.

332
00:15:12,370 --> 00:15:16,000
U nistgħu ngħidu, ġriewi
huma fuq in-naħa l-oħra.

333
00:15:16,000 --> 00:15:18,340
Allura inti biss għandek hang
fil hemm ftit itwal.

334
00:15:18,340 --> 00:15:22,050
I mean, tabilħaqq kif nibdew tranżizzjoni
fid-dinja tal-programmazzjoni web,

335
00:15:22,050 --> 00:15:26,060
inti ser issib li l-affarijiet become--
dan huwa adorable fil-fatt.

336
00:15:26,060 --> 00:15:29,680

337
00:15:29,680 --> 00:15:33,490
OK, aħna ser post dan il-URL aktar tard.

338
00:15:33,490 --> 00:15:36,140
Inti ser issib wisq li aħna qed
jintlaħaq tip ta 'plateau

339
00:15:36,140 --> 00:15:38,150
fejn kollox huwa
tabilħaqq xorta sofistikati

340
00:15:38,150 --> 00:15:40,170
u ta 'sfida minn
disinn, iżda int mhux

341
00:15:40,170 --> 00:15:42,590
se jħossu bħal aħna
perpetually jitla 'dan għoljiet.

342
00:15:42,590 --> 00:15:44,390
Sabiex jieħdu xi kumdità f'dak.

343
00:15:44,390 --> 00:15:47,409
>> Allura mingħajr aktar dewmien, ejja nibdew
biex jagħmlu din it-tranżizzjoni tas-suq

344
00:15:47,409 --> 00:15:49,950
fil-semestru għad-dinja ta '
il-web, u verament id-dinja

345
00:15:49,950 --> 00:15:51,420
li magħhom lkoll huma aktar familjari.

346
00:15:51,420 --> 00:15:53,753
Imxejna ltqajna apparati internet
fil-bwiet tagħna, fuq desks tagħna,

347
00:15:53,753 --> 00:15:55,127
fil backpacks tagħna, u simili.

348
00:15:55,127 --> 00:15:56,210
Kif ma kollha ta 'dan ix-xogħol?

349
00:15:56,210 --> 00:15:59,077
U kif nistgħu tibda bil-miktub
kodiċi li mhux super arcane

350
00:15:59,077 --> 00:16:01,910
u f'xi test Teptip fil-pront
li ebda wieħed mill-ħbieb tiegħek jew tal-familja

351
00:16:01,910 --> 00:16:04,659
qatt ser tixtieq li jinteraġixxu
ma ', imma xi ħaġa inti tista' tpoġġi

352
00:16:04,659 --> 00:16:06,660
fuq it-telefowns tagħhom, jew
fuq browsers web tagħhom,

353
00:16:06,660 --> 00:16:09,010
jew fuq kull apparat ma
li dawn jinteraġixxu.

354
00:16:09,010 --> 00:16:10,430
>> Allura hawnhekk hija dar ta 'xi ħadd.

355
00:16:10,430 --> 00:16:14,040
U ġewwa ta 'din id-dar huwa ftit
laptops, ftit desktop iskola antika

356
00:16:14,040 --> 00:16:17,470
kompjuters, xi ħaġa imsejħa
router jew buttun fin-nofs,

357
00:16:17,470 --> 00:16:20,310
u mbagħad xi tip ta '
modem tal-kejbil jew modem DSL.

358
00:16:20,310 --> 00:16:24,560
U allura hemm il-internet, ġeneralment
titpinġa bħala sħaba up hemm fis-sema.

359
00:16:24,560 --> 00:16:29,230
>> Allura din l-istampa, għalkemm
ftit tip ta datata,

360
00:16:29,230 --> 00:16:32,604
ċertament jaqbad dak li ħafna mill
inti probabilment jkollhom fid-djar tiegħek,

361
00:16:32,604 --> 00:16:35,520
jew effettivament dak kollu li għandek
fil-kmamar dorm tiegħek, jew appartamenti,

362
00:16:35,520 --> 00:16:36,480
jew simili.

363
00:16:36,480 --> 00:16:40,010
>> Allura dak li huwa attwalment għaddejjin meta
inti tipprova tuża l-Internet illum?

364
00:16:40,010 --> 00:16:42,010
Allura kull kompjuter fuq il-
internet, jirriżulta,

365
00:16:42,010 --> 00:16:46,860
jeħtieġ li jkollu indirizz uniku,
ferm simili aħna fil-ħtieġa dinja reali

366
00:16:46,860 --> 00:16:52,050
indirizz postali, bħal 51 Prospect
Street, New Haven, Connecticut, jew 33

367
00:16:52,050 --> 00:16:54,170
Oxford Street, Cambridge, Massachusetts.

368
00:16:54,170 --> 00:16:58,520
Hekk ukoll kompjuters fuq l-internet bżonn
Mod tad unikament indirizzar infushom.

369
00:16:58,520 --> 00:17:01,180
>> Li hija tant li meta wieħed kompjuter
jixtieq li jitkellmu għall-ieħor,

370
00:17:01,180 --> 00:17:04,525
dan jista 'jibgħat messaġġ u
tinforma lid-destinatarju li lilha

371
00:17:04,525 --> 00:17:05,900
għandu jibgħat ir-rispons lura.

372
00:17:05,900 --> 00:17:07,900
Allura hija biss jagħmel tip ta '
sens intuwittivi forsi

373
00:17:07,900 --> 00:17:09,980
li kollox jkollhom
indirizz ta 'xi tip.

374
00:17:09,980 --> 00:17:11,240
>> Imma kif tista 'tikseb l-indirizz?

375
00:17:11,240 --> 00:17:13,589
Ukoll, jekk ikollok hawn fuq
kampus, jew inti tmur id-dar

376
00:17:13,589 --> 00:17:15,760
u inti mbagħad fuq tiegħek
laptop jew kompjuter desktop,

377
00:17:15,760 --> 00:17:17,770
u jew plagg fil
jew qabbad lill Wi-Fi,

378
00:17:17,770 --> 00:17:19,569
jirriżulta li
hemm server speċjali

379
00:17:19,569 --> 00:17:22,089
fuq netwerks l-aktar tissejjaħ server DHCP.

380
00:17:22,089 --> 00:17:23,880
Ma verament kwistjoni
dak li dan stands għal,

381
00:17:23,880 --> 00:17:26,660
imma hija konfigurazzjoni ospitanti dinamiku
protokoll, li huwa biss

382
00:17:26,660 --> 00:17:29,760
mod fancy ta 'tgħid, dan huwa
kompjuter li jew Yale għandha,

383
00:17:29,760 --> 00:17:32,600
jew Harvard jkollu, jew Comcast
għandu, jew Verizon għandha,

384
00:17:32,600 --> 00:17:35,100
jew kumpanija tiegħek tkun,
li l-għan fil-ħajja,

385
00:17:35,100 --> 00:17:38,810
meta jisma xi ħadd ġodda miżjuda
għan-netwerk, jiġifieri hawnhekk,

386
00:17:38,810 --> 00:17:40,010
jużaw dan l-indirizz.

387
00:17:40,010 --> 00:17:42,790
>> Allura aħna bnedmin ma għandekx
kodiċi hard fis-kompjuters tagħna

388
00:17:42,790 --> 00:17:44,040
dak indirizz uniku tagħna huwa.

389
00:17:44,040 --> 00:17:47,070
Aħna biss dawwar fuq, tiftaħ il-
għatu, u b'xi mod dan is-server

390
00:17:47,070 --> 00:17:52,210
fuq in-netwerk lokali biss jgħidlekx me li
indirizz tiegħi huwa 51 Prospect Street, jew 33

391
00:17:52,210 --> 00:17:53,940
Oxford Street, jew simili.

392
00:17:53,940 --> 00:17:56,000
>> Issa mhuwiex se
jkun hekk verbose bħal dik.

393
00:17:56,000 --> 00:18:00,210
Pjuttost dak li jien ser tikseb hija
indirizz numeriku imsejħa l-indirizz IP.

394
00:18:00,210 --> 00:18:01,960
IP li jfisser internet protocol.

395
00:18:01,960 --> 00:18:06,025
U odds huma minn din id-darba fil-ħajja tiegħek,
inti probabilment jinstema 'jew jidher il-kelma IP,

396
00:18:06,025 --> 00:18:08,140
jew ġeneralment jintefa madwar forsi.

397
00:18:08,140 --> 00:18:10,720
Imma fil-fatt, huwa pjuttost
straight quddiem ħaġa.

398
00:18:10,720 --> 00:18:13,610
>> Indirizz IP huwa biss
numru deċimali bit-tikek,

399
00:18:13,610 --> 00:18:17,150
li jfisser li xi ħaġa dot
xi ħaġa dot dot xi ħaġa xi ħaġa.

400
00:18:17,150 --> 00:18:21,980
U kull wieħed minn dawk somethings jiġri
li hemm numru bejn 0 u 255.

401
00:18:21,980 --> 00:18:26,710
>> Dan ibbażati fuq ħames ġimgħat flimkien ta 'CS50, jekk
dawn in-numri kull iskala bejn 0 u 255,

402
00:18:26,710 --> 00:18:28,713
kemm bits hija kull
ta 'dawk is-sinjali in-numru?

403
00:18:28,713 --> 00:18:29,420
>> UDJENZA: Tmienja.

404
00:18:29,420 --> 00:18:30,100
>> DAVID J. Malan: Huwa ltqajna biex tkun tmienja.

405
00:18:30,100 --> 00:18:31,933
Allura b'kollox, kemm
bits huwa indirizz IP?

406
00:18:31,933 --> 00:18:32,710
UDJENZA: 32.

407
00:18:32,710 --> 00:18:33,820
>> DAVID J. Malan: Allura 32.

408
00:18:33,820 --> 00:18:35,830
8 + 8 + 8 + 8 huwa 32.

409
00:18:35,830 --> 00:18:38,767
Kemm indirizzi IP totali
jista 'jkun hemm fid-dinja?

410
00:18:38,767 --> 00:18:39,600
UDJENZA: 4 biljun.

411
00:18:39,600 --> 00:18:42,410
DAVID J. Malan: Allura madwar erba
biljun minħabba li għamilhom 2-qawwa 32.

412
00:18:42,410 --> 00:18:44,410
U jekk inti ma tistax tip ta '
grok f'moħħna tiegħek,

413
00:18:44,410 --> 00:18:47,470
biss jafu li l-valuri 32-bit
jista 'jkun kbir daqskemm 4 biljun

414
00:18:47,470 --> 00:18:49,140
jekk huwa valuri pożittivi kollha.

415
00:18:49,140 --> 00:18:52,500
Allura dan ifisser li hemm 4 biljun
indirizzi IP possibbli fid-dinja.

416
00:18:52,500 --> 00:18:55,090
>> U storja umoristiċi, aħna qed tip
ta 'tmexxija barra minnhom.

417
00:18:55,090 --> 00:18:59,720
U fil-fatt huwa problema kbira f'dak
id-dinja rat ukoll din il-problema li ġejjin,

418
00:18:59,720 --> 00:19:03,639
iżda mhux neċessarjament wieġbet għal
dan bl-aktar mod rapidu possibbli.

419
00:19:03,639 --> 00:19:05,680
U fil-fatt, ladarba inti ħadthom
lest CS50 u beda

420
00:19:05,680 --> 00:19:06,950
filwaqt li tingħata attenzjoni fil
id-dinja tech, inti ser

421
00:19:06,950 --> 00:19:08,520
tara dan huwa komuni ħafna tematika.

422
00:19:08,520 --> 00:19:12,260
>> Per eżempju, jekk immorru verament
iskola antika illum, Y2K.

423
00:19:12,260 --> 00:19:13,570
Dan ma kienx verament sorpriża.

424
00:19:13,570 --> 00:19:15,700
Bħal kulħadd kien jaf għal
1,000 sena li din

425
00:19:15,700 --> 00:19:20,250
was-- aktar minn elf years-- li
li kien eventwalment se jiġri.

426
00:19:20,250 --> 00:19:23,295
And yet, aħna wieġbet għaliha
ħafna fl-aħħar minuta.

427
00:19:23,295 --> 00:19:24,420
U li jerġa 'jseħħ.

428
00:19:24,420 --> 00:19:26,740
Hekk illum aħna ser nitkellmu dwar verżjoni IP 4.

429
00:19:26,740 --> 00:19:29,250
Iżda nafu li d-dinja
huwa finalment jkollna

430
00:19:29,250 --> 00:19:31,590
madwar biex titjib ta
xi ħaġa imsejħa IPv6,

431
00:19:31,590 --> 00:19:34,540
li minflok 32-bit
indirizzi, uses-- ħadd

432
00:19:34,540 --> 00:19:36,443
tixtieq li tieħu raden, kemm bits?

433
00:19:36,443 --> 00:19:37,310
>> UDJENZA: 64?

434
00:19:37,310 --> 00:19:38,380
>> DAVID J. Malan: raden Tajba, iżda l-ebda.

435
00:19:38,380 --> 00:19:39,975
Aħna qed finalment jipprova
jiksbu qabel il-kurva.

436
00:19:39,975 --> 00:19:40,558
>> UDJENZA: 128.

437
00:19:40,558 --> 00:19:43,490
DAVID J. Malan: 128, li
huwa numru kbir freaking

438
00:19:43,490 --> 00:19:46,250
ta 'indirizzi IP, minħabba
dan huwa simili drabi 2, darbiet 2,

439
00:19:46,250 --> 00:19:49,620
darbiet 2, ħafna drabi
twos up minn 4 biljun.

440
00:19:49,620 --> 00:19:50,530
>> Mela jekk kurjużi.

441
00:19:50,530 --> 00:19:54,110
Jirriżulta out-- u I biss Googled dan
biex isibu din out-- kompjuters Yale,

442
00:19:54,110 --> 00:19:58,910
hawn fuq Yale, għandhom tendenza li tibda bil
dawn numbers-- 130.132 dot xi ħaġa,

443
00:19:58,910 --> 00:20:00,669
u 128.36 dot xi ħaġa.

444
00:20:00,669 --> 00:20:02,710
Iżda hemm ċertament
eċċezzjonijiet madwar l-bord

445
00:20:02,710 --> 00:20:05,334
jiddependi fuq dak id-dipartiment u
bini u kampus int fuq.

446
00:20:05,334 --> 00:20:09,310
Harvard tendenza li jkollhom
140.247, jew 128.103.

447
00:20:09,310 --> 00:20:11,530
U ġeneralment dan huwa
informazzjoni inutli,

448
00:20:11,530 --> 00:20:13,260
imma hija xi ħaġa li tista 'tinnota issa.

449
00:20:13,260 --> 00:20:15,593
Meta tibda poking madwar
settings fuq il-kompjuters tiegħek,

450
00:20:15,593 --> 00:20:18,540
inti tista 'tibda l-avviż dawn
tip ta 'mudelli qabel twil.

451
00:20:18,540 --> 00:20:23,470
>> Imma meta int fid-dar u jkollhom
Apple Ajruport, jew apparat Linksys,

452
00:20:23,470 --> 00:20:26,560
jew D-Link, jew kwalunkwe huwa
ġenituri tiegħek jew aħwa installati

453
00:20:26,560 --> 00:20:28,890
fid-dar tiegħek, ukoll
dak li probabilment jkollhom

454
00:20:28,890 --> 00:20:30,800
huwa dak li sejjaħ indirizz IP privat.

455
00:20:30,800 --> 00:20:34,850
U dawn kienu fil-fatt
sbieħ, soluzzjoni temporanja

456
00:20:34,850 --> 00:20:38,050
għall-problema ta 'tmexxija
qasir fuq indirizzi IP.

457
00:20:38,050 --> 00:20:40,382
>> U x'tista 'tagħmel ma
netwerks dar, typically--

458
00:20:40,382 --> 00:20:42,340
u franchement, anki Yale
u Harvard qed jibdew

459
00:20:42,340 --> 00:20:46,840
biex jagħmlu dan fil areas-- differenti huwa inti
jistgħu jagħtu mazz sħiħ ta 'kompjuters

460
00:20:46,840 --> 00:20:50,360
waħda indirizz IP sakemm inti tpoġġi
apparat speċjali ta 'quddiemhom,

461
00:20:50,360 --> 00:20:52,410
xi ħaġa imsejħa router,
jew jista 'jissejjaħ

462
00:20:52,410 --> 00:20:54,060
prokuratur jew kwalunkwe numru ta 'affarijiet oħra.

463
00:20:54,060 --> 00:20:56,710
Iżda mezz ċerti li
għandha dak l-indirizz IP wieħed.

464
00:20:56,710 --> 00:20:59,450
U mbagħad wara li
apparat, ġewwa bini,

465
00:20:59,450 --> 00:21:03,030
fi dar jew appartament, jista 'jkun
kwalunkwe numru ta 'kompjuters, li kollha

466
00:21:03,030 --> 00:21:06,460
jkollu indirizz IP li tibda
ma 'waħda minn dawn ċifri hawn.

467
00:21:06,460 --> 00:21:08,590
U sakemm li l-kompjuter
jaf kif jikkonvertu

468
00:21:08,590 --> 00:21:10,900
-indirizz pubbliku li
l-indirizz privat,

469
00:21:10,900 --> 00:21:13,340
kollox jista sort ta 'xogħol kif mistenni.

470
00:21:13,340 --> 00:21:17,290
>> Iżda l-maqlub ta 'dan huwa li jekk
int fid-dar u inti għandek parentela,

471
00:21:17,290 --> 00:21:19,650
u tnejn inti
jżuru xi website,

472
00:21:19,650 --> 00:21:23,520
din il-websajt ma jafx jekk huwa inti
jew aħwa tiegħek jżuru l-websajt,

473
00:21:23,520 --> 00:21:26,780
għaliex inti jidhru li huma l-istess
persuna minħabba kollha tad-data tiegħek

474
00:21:26,780 --> 00:21:30,050
hija għaddejja li router
jew dak il-punt ċentrali.

475
00:21:30,050 --> 00:21:32,220
>> Iżda biżżejjed fuq dawn id-dettalji livell aktar baxx.

476
00:21:32,220 --> 00:21:37,770
Ejja tagħti ħarsa lejn indirizzi IP kif
kultant toħroġ forsi fil-midja

477
00:21:37,770 --> 00:21:41,370
u kif aħna issa jistgħu jibdew rovina,
Franchement, saħansitra aktar turi għalik.

478
00:21:41,370 --> 00:21:45,010
Jekk nistgħu dim l
Dwal għal ftit sekondi.

479
00:21:45,010 --> 00:21:46,550
>> [Daqq video]

480
00:21:46,550 --> 00:21:49,310
>> -Hija L 32-daqsxejn fuq IPP 4 indirizz.

481
00:21:49,310 --> 00:21:50,650
>> -IP ES internet--

482
00:21:50,650 --> 00:21:52,800
>> Network -Private,
Netwerk privat Tamia tal.

483
00:21:52,800 --> 00:22:05,670

484
00:22:05,670 --> 00:22:08,145
Hija hekk aqwa.

485
00:22:08,145 --> 00:22:09,630
-Come Fuq Charlie.

486
00:22:09,630 --> 00:22:11,750
DAVID J. Malan: Huwa
indirizz IP mera.

487
00:22:11,750 --> 00:22:15,093
Hi tal kiri us watch li
hi qed jagħmel fil-ħin reali.

488
00:22:15,093 --> 00:22:16,285
>> [END Daqq]

489
00:22:16,285 --> 00:22:17,130
>> DAVID J. Malan: OK.

490
00:22:17,130 --> 00:22:18,480
Allura ftit problemi ma 'dan.

491
00:22:18,480 --> 00:22:22,740
Allura wieħed, dak li aħna qed tfittex
fil hawn fuq l-iskrin

492
00:22:22,740 --> 00:22:25,290
huwa kodiċi miktub fil-
lingwa imsejħa Objettiv-C,

493
00:22:25,290 --> 00:22:28,020
li huwa tip ta 'suċċessur għall
il-lingwa C li aħna qed isir.

494
00:22:28,020 --> 00:22:30,150
Dan għandu assolutament xejn
x'jaqsmu ma 'l-ipprogrammar.

495
00:22:30,150 --> 00:22:32,399
Fil-fatt, bħala l-aħjar I tista 'tgħid,
dan huwa programm tpinġija

496
00:22:32,399 --> 00:22:38,360
li xi ħadd jitniżżel mill-
internet b'xi jinvolvu krejons.

497
00:22:38,360 --> 00:22:43,660
>> Forsi inqas agħar huwa li
dan l-indirizz IP, validu jew invalidi?

498
00:22:43,660 --> 00:22:44,520
>> UDJENZA: Invalid.

499
00:22:44,520 --> 00:22:48,479
>> DAVID J. Malan: invalida, għaliex 275
huwa, ovvjament, mhux bejn 0 u 255.

500
00:22:48,479 --> 00:22:51,770
Li wisq huwa probabbilment OK għalkemm, minħabba
inti ma tridx li mazz ta 'nies crazy

501
00:22:51,770 --> 00:22:54,790
li huma simili jieqaf TV fuq tagħhom
TiVos u mbagħad jżuru l-IP biex tara

502
00:22:54,790 --> 00:22:56,290
jekk hemm attwalment xi ħaġa hemmhekk.

503
00:22:56,290 --> 00:22:58,200
Hekk li wieħed huwa ftit inqas agħar.

504
00:22:58,200 --> 00:23:00,990
Iżda jirrealizzaw li wisq huwa
tip ta 'kollha madwarna.

505
00:23:00,990 --> 00:23:04,980
>> Allura naturalment, ħadd minna qatt
verament tip indirizzi numeriċi

506
00:23:04,980 --> 00:23:06,410
fis browsers tagħna.

507
00:23:06,410 --> 00:23:09,580
Ikun tip ta 'ħaġa ħażina
jekk Google, li jżuru Google,

508
00:23:09,580 --> 00:23:15,060
inti kellha tmur 123.46.57.89.

509
00:23:15,060 --> 00:23:17,007
U d-dinja kollha kellhom
li biss ftakar li.

510
00:23:17,007 --> 00:23:19,090
U franchement, konna tip
ta rajt din il-kwistjoni qabel.

511
00:23:19,090 --> 00:23:24,130
Lura fil-ġurnata meta n-nies ma
jkollhom cell phones u listi ta 'kuntatt,

512
00:23:24,130 --> 00:23:27,640
u l-kumpaniji attwalment still-- attwalment,
I raden kumpaniji għad għandhom 800

513
00:23:27,640 --> 00:23:30,600
numri u l like-- imma inti
ġeneralment tara numri reklamati

514
00:23:30,600 --> 00:23:36,480
kif 1-800-Iġbor, C-O-L-L-E-C-T.
Minħabba li ebda wieħed jista 'verament tiftakar,

515
00:23:36,480 --> 00:23:39,754
meta jaraw reklam fuq bus
jew kartellun, dak li xi ħadd numru huwa,

516
00:23:39,754 --> 00:23:42,420
iżda jistgħu probabbilment, ma ogħla
probabbiltà, ftakar kelma.

517
00:23:42,420 --> 00:23:44,530
>> Allura aħna adottaw l-istess
tip ta 'sistema fid-dinja

518
00:23:44,530 --> 00:23:48,290
tal-internet li permezz tiegħu hemm
sistema isem tad-dominju sabiex aħna bnedmin tista

519
00:23:48,290 --> 00:23:52,340
tip google.com, facebook.com,
yale.edu, harvard.edu,

520
00:23:52,340 --> 00:23:56,140
u ħalli l-figura kompjuters
barra dak l-IP korrispondenti

521
00:23:56,140 --> 00:23:58,480
indirizz huwa għal isem partikolari.

522
00:23:58,480 --> 00:24:01,620
>> U l-mod inti tagħmel dan fil-
dinja reali hija li għal $ 10 a sena,

523
00:24:01,620 --> 00:24:05,900
forsi $ 50 a sena, inti tista 'tixtri dominju
isem, jew verament kera isem ta 'dominju.

524
00:24:05,900 --> 00:24:09,860
U allura min qed tħallas
li l-kera dak l-isem tad-dominju,

525
00:24:09,860 --> 00:24:14,069
inti jgħidulhom li fid-dinja
jaf liema indirizz IP tiegħek huwa.

526
00:24:14,069 --> 00:24:16,360
U aħna mhux se tidħol fis dawn
dettalji, imma ħafna minnkom

527
00:24:16,360 --> 00:24:18,750
jista 'jkun irid, per finali
proġetti, li attwalment jiffirmaw

528
00:24:18,750 --> 00:24:22,120
għall-web hosting tiegħek stess
kumpanija, jew b'xejn

529
00:24:22,120 --> 00:24:23,500
jew għal ftit dollari fix-xahar.

530
00:24:23,500 --> 00:24:26,100
Xi wħud minnkom tista 'tixtieq li jixtru, għall
ftit dollari, l-isem tad-dominju tiegħek stess,

531
00:24:26,100 --> 00:24:28,900
biss għall-gost jew li jibdew negozju
jew sit personali jew simili.

532
00:24:28,900 --> 00:24:30,880
>> U jirrealizzaw li l
ta 'li se finalment

533
00:24:30,880 --> 00:24:35,260
jsarrafx biss fl lilek javżak-dinja
liema server tiegħek indirizz IP hu.

534
00:24:35,260 --> 00:24:37,740
U mbagħad dawn DNS
servers attwalment jieħdu ħsieb

535
00:24:37,740 --> 00:24:39,910
sabiex jinforma lill-bqija tad-dinja.

536
00:24:39,910 --> 00:24:41,830
Allura kull server DNS
għandha, fil-qosor, ġewwa

537
00:24:41,830 --> 00:24:44,780
tal-memorja tagħha huwa bħall-
ekwivalenti ta 'spreadsheet Google

538
00:24:44,780 --> 00:24:49,420
jew spreadsheet Excel b'mill-inqas
żewġ kolonni, waħda minnhom ismijiet,

539
00:24:49,420 --> 00:24:52,100
bħall harvard.edu, u
yale.edu, u google.com.

540
00:24:52,100 --> 00:24:55,870
U l-kolonna ieħor għandha l-
indirizz IP jew IP korrispondenti

541
00:24:55,870 --> 00:24:56,382
indirizzi.

542
00:24:56,382 --> 00:24:57,590
U nistgħu ngħidu tara dan.

543
00:24:57,590 --> 00:24:59,881
Allura fuq Mac-- tiegħi u inti tista
tagħmel dan fuq kompjuters Windows

544
00:24:59,881 --> 00:25:04,330
kif well-- jekk I tiftaħ tieqa terminal
hawn, pjuttost bħal dak fil CD50 IDE,

545
00:25:04,330 --> 00:25:08,190
kompjuters aktar ikollhom kmand imsejħa
nslookup, isem server tfittex up.

546
00:25:08,190 --> 00:25:12,380
U jekk jien tip xi ħaġa fil bħal
yale.edu u hit Ikteb, liema

547
00:25:12,380 --> 00:25:19,250
I għandha tara jekk in-netwerk tiegħi tikkoopera kif
hija għamlet għal testijiet multipli qabel klassi

548
00:25:19,250 --> 00:25:24,584
began-- ejja jippruvaw google.com.

549
00:25:24,584 --> 00:25:26,390
Of course issa xejn ta 'ħidma.

550
00:25:26,390 --> 00:25:27,190
Li l-kbir.

551
00:25:27,190 --> 00:25:30,660
Kull dritt, stand mill għal mument wieħed.

552
00:25:30,660 --> 00:25:32,100
nslookup google.com.

553
00:25:32,100 --> 00:25:35,570

554
00:25:35,570 --> 00:25:38,660
>> Well, ejja ara jekk il-
internet-- ebda attwali.

555
00:25:38,660 --> 00:25:39,700
Dan huwa dak li ġara.

556
00:25:39,700 --> 00:25:43,090
Oh my god, id-dritt.

557
00:25:43,090 --> 00:25:45,490
Il Wi-Fi kissru.

558
00:25:45,490 --> 00:25:47,410
>> Ħej, trid tkun taf liema indirizz IP tiegħi huwa?

559
00:25:47,410 --> 00:25:49,722
Kull dritt.

560
00:25:49,722 --> 00:25:50,820
YaleSecure.

561
00:25:50,820 --> 00:25:53,330
Din hija kif inti troubleshoot
affarijiet kif xjenzat kompjuter.

562
00:25:53,330 --> 00:25:54,617
Ngħaddu l Wi-Fi off.

563
00:25:54,617 --> 00:25:57,480

564
00:25:57,480 --> 00:25:59,450
KOLLOX SEW.

565
00:25:59,450 --> 00:26:02,610
>> U fil-fatt, Scaz, do you mind
qtugħ us fil-wieħed sigur?

566
00:26:02,610 --> 00:26:06,246
Testijiet inkella aktar are-- OK, nirringrazzja
inti Yale-- jew ikun sejjer jinkiser.

567
00:26:06,246 --> 00:26:07,370
Irrid immur fuq YaleSecure.

568
00:26:07,370 --> 00:26:09,880

569
00:26:09,880 --> 00:26:11,870
Oh, u forsi aħna ser tkun OK.

570
00:26:11,870 --> 00:26:12,686
Forsi aħna qed lura.

571
00:26:12,686 --> 00:26:16,810

572
00:26:16,810 --> 00:26:19,733
U li kif, bħala kompjuter
xjentist jiffissaw kompjuter.

573
00:26:19,733 --> 00:26:22,000
[Applause]

574
00:26:22,000 --> 00:26:23,220
Kull dritt.

575
00:26:23,220 --> 00:26:27,160
Għalhekk, fejn I kien fi ħdan dan
hekk imsejħa tieqa terminal,

576
00:26:27,160 --> 00:26:32,270
u jekk jien nslookup
yale.edu, hemm immorru.

577
00:26:32,270 --> 00:26:38,350
So I nikseb lura ewwel-indirizz IP ta '
is-server DNS li laptop tiegħi qed tuża.

578
00:26:38,350 --> 00:26:41,610
Allura flimkien ma 'server DHCP li
tkellimna dwar mument ilu javżak

579
00:26:41,610 --> 00:26:44,720
dak laptop tiegħi IP tiegħi
indirizz huwa, li server DHCP

580
00:26:44,720 --> 00:26:46,860
wkoll jgħidlekx me dak DNS server għall-użu.

581
00:26:46,860 --> 00:26:48,860
Inkella I jkollhom
li manwalment tip dan.

582
00:26:48,860 --> 00:26:50,359
>> Imma dak li mhux kollha li interessanti.

583
00:26:50,359 --> 00:26:54,310
What I kura dwar huwa li dan huwa l-
Indirizz IP ta 'website Yale apparentament.

584
00:26:54,310 --> 00:26:55,470
Allura fil-fatt, ejja ipprova din.

585
00:26:55,470 --> 00:27:02,710
Let me go up fis browser u jmorru
http: //, u mbagħad dak l-indirizz IP,

586
00:27:02,710 --> 00:27:04,220
u hit Ikteb.

587
00:27:04,220 --> 00:27:06,700
U jgħidilna tara.

588
00:27:06,700 --> 00:27:09,587
Dan huwa kif inkella inti tista
żur il-websajts Yale s.

589
00:27:09,587 --> 00:27:10,920
Issa huwa mhux kollha li memorabbli.

590
00:27:10,920 --> 00:27:12,220
Simili, il-frosh pre
probabbilment mhumiex se

591
00:27:12,220 --> 00:27:15,310
li tiftakar dan l-indirizz partikolari
jekk qallek li jżuru hemm wara li jżuru.

592
00:27:15,310 --> 00:27:16,580
Iżda dan ma jidhirx li jaħdmu.

593
00:27:16,580 --> 00:27:21,179
U hekk DNS verament ftit jippermetti li
għandhom ħafna aktar indirizzi ħbiberija bniedem.

594
00:27:21,179 --> 00:27:23,220
Iżda dawn ma jkunux neċessarjament
biss rendiment tweġiba waħda.

595
00:27:23,220 --> 00:27:25,640
>> Fil-fatt, meta int
verament teknoloġija għolja kbar,

596
00:27:25,640 --> 00:27:27,620
inti probabilment tixtieq li
jkollhom lottijiet ta 'servers.

597
00:27:27,620 --> 00:27:29,027
U anki dan huwa qarrieqi.

598
00:27:29,027 --> 00:27:31,110
Allura Yale probabbilment ma
għadek web server wieħed.

599
00:27:31,110 --> 00:27:34,150
Google probabbilment ma jkollux
biss 10 jew hekk servers mill-web.

600
00:27:34,150 --> 00:27:36,960
Google speċjalment probabbilment
għandha eluf ta 'servers mill-web

601
00:27:36,960 --> 00:27:40,030
madwar id-dinja li jistgħu jirrispondu
għal talbiet minn nies bħalna.

602
00:27:40,030 --> 00:27:43,870
>> Iżda huma wkoll jużaw teknoloġija msejħa
ibbilanċjar tat-tagħbija, li storja twila fil-qosor,

603
00:27:43,870 --> 00:27:48,810
għandha biss mezzi ftit fid-dinja
tixrid tal-piż madwar servers aktar.

604
00:27:48,810 --> 00:27:52,320
Allura huwa tip simili ta 'web spider jekk
inti ser jintbagħtu l talbiet.

605
00:27:52,320 --> 00:27:54,380
Iżda għal issa, dak kollu li huwa
interessanti għal-lum

606
00:27:54,380 --> 00:27:56,870
hija li isem ta 'dominju
bħal google.com anke jista

607
00:27:56,870 --> 00:28:00,100
jkollhom indirizzi IP multipli bħal dik.

608
00:28:00,100 --> 00:28:04,610
>> Imma kif ma kollha ta 'data tagħna attwalment
jiksbu quddiem u lura mbagħad fl-aħħar?

609
00:28:04,610 --> 00:28:08,320
Ukoll, jirriżulta li hemm dawn
affarijiet imsejħa routers fuq l-internet.

610
00:28:08,320 --> 00:28:10,980
U dak huwa router għall-
limitu li inti taf diġà?

611
00:28:10,980 --> 00:28:13,730
U stajt użat il-kelma koppja
drabi fil-kuntest ta 'dar,

612
00:28:13,730 --> 00:28:17,155
iżda f'termini sempliċi,
dak ma router do?

613
00:28:17,155 --> 00:28:18,780
Agħti me biss raden bbażata fuq isimha?

614
00:28:18,780 --> 00:28:20,082
>> UDJENZA: Allura triq jew triq?

615
00:28:20,082 --> 00:28:21,790
DAVID J. Malan: Allura
huwa triq jew triq.

616
00:28:21,790 --> 00:28:23,980
Allura rotta hija triq
jew il-passaġġ, assolutament.

617
00:28:23,980 --> 00:28:27,000
U router, hekk mezz li
attwalment rotot informazzjoni,

618
00:28:27,000 --> 00:28:29,690
se jimxu data bejn punti A u B.

619
00:28:29,690 --> 00:28:31,920
>> U hekk fl fact-- u
dan huwa forsi meta

620
00:28:31,920 --> 00:28:34,510
inti Google xbihat ta routers
fuq id-dinja, inti kollha jiksbu

621
00:28:34,510 --> 00:28:35,900
huma dijagrammi marketing Logged.

622
00:28:35,900 --> 00:28:38,550
U għalhekk dan huwa tip ta 'l-aktar
rappreżentant wieħed I jista 'jsib

623
00:28:38,550 --> 00:28:39,841
li ħares kemmxejn interessanti.

624
00:28:39,841 --> 00:28:44,170
Kull wieħed minn dawn tikek jew glimmers ta 'tama
madwar id-dinja jirrappreżenta router.

625
00:28:44,170 --> 00:28:47,210
U kull wieħed minnhom għandha linja
bejn xi router oħra.

626
00:28:47,210 --> 00:28:49,090
>> Minħabba fil-fatt, hemm
eluf, probabbilment

627
00:28:49,090 --> 00:28:52,560
miljuni ta 'routers madwar id-
dinja, li wħud minnhom huma fid-djar tagħna

628
00:28:52,560 --> 00:28:56,070
u fuq il-kampus tagħna, iżda ħafna ta '
li huma proprjetà ta 'kumpaniji kbar

629
00:28:56,070 --> 00:29:00,250
u huma interkonnessi b'tali mod li jekk I
trid tibgħat xi data minn hawn fil-Yale

630
00:29:00,250 --> 00:29:04,430
dar lura lejn Cambridge, Yale probabbilment
ma jkollux kejbil uniku, ċertament,

631
00:29:04,430 --> 00:29:05,650
jmorru direttament għand Harvard.

632
00:29:05,650 --> 00:29:07,399
U Yale ma jkollux
kejbil uniku tmur

633
00:29:07,399 --> 00:29:10,010
MIT, jew li Stanford, jew
Berkeley, jew li Google,

634
00:29:10,010 --> 00:29:11,820
jew kwalunkwe numru ta 'destinazzjonijiet.

635
00:29:11,820 --> 00:29:14,760
>> Pjuttost, Yale, u Harvard, u
kulħadd fuq l-internet

636
00:29:14,760 --> 00:29:17,610
ma jkollu routers wieħed jew aktar
konnessi magħha, forsi

637
00:29:17,610 --> 00:29:18,810
fuq il-periferija ta 'kampus.

638
00:29:18,810 --> 00:29:21,690
B'tali mod li meta d-data tiegħi trid
li jħallu kampus Yale, il

639
00:29:21,690 --> 00:29:24,770
din tmur għal dak router eqreb,
kif muri minn wieħed minn dawn tikek.

640
00:29:24,770 --> 00:29:27,940
U mbagħad l-figuri router minn jekk
tibgħat dan il-mod, jew b'dan il-mod,

641
00:29:27,940 --> 00:29:33,440
jew b'dan il-mod, jew dan il-mod ibbażati
fuq il-mejda ieħor fil-memorja tiegħu,

642
00:29:33,440 --> 00:29:36,870
fajl Excel ieħor jew Google
spreadsheet li f'kolonna waħda

643
00:29:36,870 --> 00:29:41,315
jgħid, jekk l-indirizz IP tiegħek tibda
bin-numru wieħed, mur dan il-mod.

644
00:29:41,315 --> 00:29:43,690
Jekk l-indirizz IP tiegħek tibda bil
numru tnejn, jmorru mod.

645
00:29:43,690 --> 00:29:47,040
U għalhekk inti tista 'tinqasam
numerikament li jkollhom l-router jibgħat

646
00:29:47,040 --> 00:29:49,040
data kull mod.

647
00:29:49,040 --> 00:29:51,419
>> U nistgħu tip ta 'tara dan ukoll.

648
00:29:51,419 --> 00:29:54,210
Ejja imorru quddiem fis dan terminali
tieqa darb'oħra, u let me jimxi 'l quddiem

649
00:29:54,210 --> 00:30:00,700
u traċċa ir-rotta li,
ejja ngħidu, www.mit.edu,

650
00:30:00,700 --> 00:30:02,970
li huwa ftit mijiet mili bogħod.

651
00:30:02,970 --> 00:30:04,500
Dan kien verament kkritikat mgħaġġel.

652
00:30:04,500 --> 00:30:06,290
>> Allura dak li ġara biss?

653
00:30:06,290 --> 00:30:10,360
Allura fi ftit seba 'passi, u
fil biss erba millisekondi,

654
00:30:10,360 --> 00:30:14,660
I bagħtet data fuq l-internet
minn hawn fil-Yale biex MIT.

655
00:30:14,660 --> 00:30:18,240
Kull wieħed minn dawn ringieli, inti tista
forsi raden issa jirrappreżenta dak?

656
00:30:18,240 --> 00:30:19,060
>> UDJENZA: A router.

657
00:30:19,060 --> 00:30:20,101
>> DAVID J. Malan: A router.

658
00:30:20,101 --> 00:30:24,090
Allura fil-fatt, jidher qisu hemm
madwar seba 'jew hekk routers,

659
00:30:24,090 --> 00:30:29,350
jew sitt routers fil bejni
fiżikament fl-iskola liġi Yale hawn

660
00:30:29,350 --> 00:30:31,612
u l-websajt MIT hemmhekk.

661
00:30:31,612 --> 00:30:34,570
U dak li nistgħu glean minn dan huwa
kif follows-- u let me inaddfu up.

662
00:30:34,570 --> 00:30:38,180
Jien ser terġa 'ssir bl kmand
argument linja tal q 1 sa biss jgħidu,

663
00:30:38,180 --> 00:30:39,300
biss jagħtu me mistoqsija waħda.

664
00:30:39,300 --> 00:30:40,800
Konvenzjonalment, traċċa rotta ma tlieta.

665
00:30:40,800 --> 00:30:42,350
U hu għalhekk li rajna
għenieqed ta 'numri.

666
00:30:42,350 --> 00:30:44,850
Irrid nara inqas numri
biss biex iżommu l-aktar nodfa output.

667
00:30:44,850 --> 00:30:46,280
U ejja ara dak li jiġri.

668
00:30:46,280 --> 00:30:49,220
>> Allura għal kwalunkwe raġuni,
xi ħadd fil-ħsieb Yale

669
00:30:49,220 --> 00:30:54,130
ikun umoristiċi li hija sejħa tiegħek
default router arubacentral, li

670
00:30:54,130 --> 00:30:57,920
huwa fuq vlan jew virtwali
LAN, żona lokali virtwali

671
00:30:57,920 --> 00:30:59,810
network 30-- sabiex inti
probabilment jkollhom mill-inqas

672
00:30:59,810 --> 00:31:03,050
29 router.net.yale.internal others--.

673
00:31:03,050 --> 00:31:06,660
U .internal hawnhekk hija tip ta 'foloz
top dominju livell maħsuba biex jintużaw biss

674
00:31:06,660 --> 00:31:07,210
fuq il-kampus.

675
00:31:07,210 --> 00:31:10,335
U avviż l-indirizz IP korrispondenti
ta 'dak router, kull fejn huwa hawnhekk

676
00:31:10,335 --> 00:31:13,920
fuq il-kampus, huwa 172.28.204.129.

677
00:31:13,920 --> 00:31:17,470
U hija ħadet 36 millisekondi
li jmorru minn hawn għal hemm.

678
00:31:17,470 --> 00:31:18,050
>> Storja umoristiċi.

679
00:31:18,050 --> 00:31:19,716
Aħna ser terġa 'lura li fi ftit mument.

680
00:31:19,716 --> 00:31:22,920
Imma issa t-tieni router-- li
li arubacentral apparentement

681
00:31:22,920 --> 00:31:25,790
għandu xi tip ta 'fiżiku
konnessjoni aktar likely--

682
00:31:25,790 --> 00:31:27,249
l-bnedmin ma jolqot tismija.

683
00:31:27,249 --> 00:31:30,373
Il-bnedmin Yale ma jolqot tismija
huwa għaliex dan huwa ġewwa ta 'network tiegħek

684
00:31:30,373 --> 00:31:30,940
jidher.

685
00:31:30,940 --> 00:31:32,520
U għalhekk hija biss għandha l-indirizz IP.

686
00:31:32,520 --> 00:31:34,660
>> Iżda mbagħad terz router
hawn fuq network Yale

687
00:31:34,660 --> 00:31:36,700
li probabbilment ftit
farther bogħod xorta

688
00:31:36,700 --> 00:31:41,330
huwa msejjaħ cen10g x'ikun
jiġifieri asr.net.yale.internal.

689
00:31:41,330 --> 00:31:43,040
U wisq għandha l-indirizz IP.

690
00:31:43,040 --> 00:31:44,990
>> Issa għaliex huma dawn in-numri
tip ta 'tvarja?

691
00:31:44,990 --> 00:31:47,890
2.9, 1.4, 36?

692
00:31:47,890 --> 00:31:48,840
Routers tikseb busy.

693
00:31:48,840 --> 00:31:50,420
U huma jiksbu konġestjoni u appoġġjata.

694
00:31:50,420 --> 00:31:53,200
Hemm eluf ta 'nies fuq din
kampus jużaw l-internet dritt issa.

695
00:31:53,200 --> 00:31:56,050
Hemm mitt ruħ f'din
kamra jużaw l-internet dritt issa.

696
00:31:56,050 --> 00:31:59,030
>> U hekk dak li qed jiġri hu li
l routers tista 'tikseb konġestjoni.

697
00:31:59,030 --> 00:32:01,350
U hekk dawk il-ħinijiet jista
ivarjaw ftit.

698
00:32:01,350 --> 00:32:04,620
Allura hu għalhekk dawn ma neċessarjament
jżidu jinftiehem.

699
00:32:04,620 --> 00:32:07,510
>> Imma l-affarijiet nikseb tip ta '
interessanti fil-pass erbgħa.

700
00:32:07,510 --> 00:32:13,040
Apparentement bejn Yale u
pass erba huwa hop ieħor.

701
00:32:13,040 --> 00:32:16,480
U fejn huwa l-router
fil-pass erba probabbilment?

702
00:32:16,480 --> 00:32:17,410
>> UDJENZA: [inaudible]

703
00:32:17,410 --> 00:32:19,410
>> DAVID J. Malan: JFK forsi,
forsi fl-ajruport.

704
00:32:19,410 --> 00:32:21,950
Iżda għal xi raġuni,
amministraturi tas-sistema, sabiex

705
00:32:21,950 --> 00:32:24,140
geeks li jaħdmu servers għall
snin ikunu semmew routers

706
00:32:24,140 --> 00:32:25,600
wara l-eqreb kodiċi ajruport.

707
00:32:25,600 --> 00:32:27,420
Allura JFK probabbilment ifisser
huwa biss x'imkien

708
00:32:27,420 --> 00:32:29,970
fi New York, forsi fil Manhattan
jew wieħed mill-boroughs.

709
00:32:29,970 --> 00:32:34,460
nyc2 tindika, preżumibbilment, ieħor
router li x'imkien fi New York.

710
00:32:34,460 --> 00:32:37,140
>> I do not pjuttost taf fejn ringiela
sitt hija hawnhekk, numru router sitta.

711
00:32:37,140 --> 00:32:40,110
quest.net ISP kbar,
fornitur tas-servizz internet,

712
00:32:40,110 --> 00:32:43,240
li jipprovdi konnettività internet
għall-postijiet kbar bħal Yale u oħrajn.

713
00:32:43,240 --> 00:32:47,110
U allura dan l-aħħar wieħed,
Dehra dik MIT lanqas ma

714
00:32:47,110 --> 00:32:50,180
għandhom websajt tagħhom
fil Cambridge neċessarjament,

715
00:32:50,180 --> 00:32:52,090
iżda pjuttost li ħadthom
esternalizzati websajt tagħhom,

716
00:32:52,090 --> 00:32:55,150
jew għall-inqas l-servers fiżiċi,
lil kumpanija msejħa Akamai.

717
00:32:55,150 --> 00:32:57,940
U Akamai fatt hu dritt isfel
it-triq minn MIT fil Cambridge

718
00:32:57,940 --> 00:32:58,790
jirriżulta.

719
00:32:58,790 --> 00:33:02,360
>> Iżda jirrealizzaw wisq li anke ħsibt
int ser www.mit.edu,

720
00:33:02,360 --> 00:33:05,200
nistgħu verament jintbagħtu
kullimkien fid-dinja.

721
00:33:05,200 --> 00:33:06,960
>> U ejja ara x'imkien
ieħor fid-dinja.

722
00:33:06,960 --> 00:33:09,240
Let me imorru quddiem u ċara
dan l-iskrin u minflok

723
00:33:09,240 --> 00:33:15,240
traċċa ir-rotta, darba biss, hekk
query waħda, li www.cnn.co.jp,

724
00:33:15,240 --> 00:33:18,390
il-home page Ġappuniż
għall CNN, is-sit aħbarijiet.

725
00:33:18,390 --> 00:33:20,660
U jekk I hit Ikteb issa,
ejja ara dak li jiġri.

726
00:33:20,660 --> 00:33:23,610
Aħna darb'oħra jibdew minn arubacentral.

727
00:33:23,610 --> 00:33:26,510
Aħna mbagħad tmur għall-
router nameless, ftit aktar.

728
00:33:26,510 --> 00:33:29,527
Allura huwa ħa 12 hops li
jiksbu l-Ġappun dan iż-żmien.

729
00:33:29,527 --> 00:33:30,860
U ejja ara dak li nistgħu glean.

730
00:33:30,860 --> 00:33:32,450
>> Allura istess hop,-istess hop.

731
00:33:32,450 --> 00:33:35,170
Kemmxejn differenti issa.

732
00:33:35,170 --> 00:33:36,380
Dan wieħed interessanti.

733
00:33:36,380 --> 00:33:40,870
Hekk jien guessing hawn, stamford1 hija
ftit bliet bogħod fil Connecticut wkoll.

734
00:33:40,870 --> 00:33:43,810
Dawn routers f'sitt ringiela
u sebgħa ma għandhom ismijiet.

735
00:33:43,810 --> 00:33:46,370
Iżda din hija tip tal-aqwa.

736
00:33:46,370 --> 00:33:53,310
>> Allura dak li jidher li jkun bejn il-
routers fil-pass seba u tmien?

737
00:33:53,310 --> 00:33:54,760
U għaliex do you say kemm?

738
00:33:54,760 --> 00:33:55,260
Yeah?

739
00:33:55,260 --> 00:33:56,060
>> UDJENZA: Oċean.

740
00:33:56,060 --> 00:33:57,640
>> DAVID J. Malan: Probabbilment oċean.

741
00:33:57,640 --> 00:34:01,366
Aħna nafu li veru
simili, intuwittivament, right?

742
00:34:01,366 --> 00:34:04,790
Iżda nistgħu nikkonfermaw tip kemm
tal tip ta 'empiriku għaliex?

743
00:34:04,790 --> 00:34:06,860
Dak li nbidlet bejn
ringieli seba 'u tmien?

744
00:34:06,860 --> 00:34:09,429

745
00:34:09,429 --> 00:34:14,739
>> Hija ħadet ħafna aktar ħin biex tmur
tkun xi tkun din router nameless seba hija,

746
00:34:14,739 --> 00:34:18,670
probabbilment x'imkien fil-
kontinentali Istati Uniti, li pass tmienja,

747
00:34:18,670 --> 00:34:22,639
li hija probabbilment x'imkien fil-Ġappun
ibbażata fuq l-isem tad-dominju tal .jp hemmhekk.

748
00:34:22,639 --> 00:34:25,719
U sabiex dawk addizzjonali
mitt millisekondi xi ħaġa

749
00:34:25,719 --> 00:34:28,960
jew 90 jew hekk millisekondi hija
ir-riżultat ta 'data tagħna tmur

750
00:34:28,960 --> 00:34:31,100
fuq korp pretty kbir ta 'ilma.

751
00:34:31,100 --> 00:34:34,570
>> Issa curiously, jidher li forsi
li cable tmur madwar l-Istati Uniti kollu.

752
00:34:34,570 --> 00:34:37,070
Jekk aħna qed attwalment għaddejjin fuq
l Kosta tal-Punent biex tikseb il-Ġappun,

753
00:34:37,070 --> 00:34:39,111
huwa tip ta 'l-bogħod
jekk irridu jmorru l-mod ieħor.

754
00:34:39,111 --> 00:34:41,400
Għalhekk mhuwiex ċar għal kollox
x'inhu għaddej fiżikament.

755
00:34:41,400 --> 00:34:43,830
Imma l-fatt li kull
hop addizzjonali tabilħaqq

756
00:34:43,830 --> 00:34:46,020
ħa sew itwal
minn kull oħra, huwa

757
00:34:46,020 --> 00:34:50,440
pretty konferma tajba li s CNN
Web server Ġappuniż huwa probabbilment tabilħaqq

758
00:34:50,440 --> 00:34:51,310
fil-Ġappun.

759
00:34:51,310 --> 00:34:54,089
U huwa ċertament farther
bogħod milli MIT kienet.

760
00:34:54,089 --> 00:34:56,380
U huwa ta 'min jinnota wkoll,
data tiegħek mhux bilfors

761
00:34:56,380 --> 00:34:58,794
tmur għall-ivvjaġġar tal-
iqsar distanza possibbli.

762
00:34:58,794 --> 00:35:00,960
Fil-fatt, jekk inti play madwar
ma traċċa rotta fid-dar

763
00:35:00,960 --> 00:35:04,170
biss picking websajts każwali, inti
tista 'ssib li biss tibgħat email

764
00:35:04,170 --> 00:35:06,490
jew biex iżuru website
li l-hawn fi New Haven,

765
00:35:06,490 --> 00:35:09,200
kultant data tiegħek jista ewwel
jieħdu dawra, jinżlu għal DC,

766
00:35:09,200 --> 00:35:10,450
u mbagħad jiġu lura up.

767
00:35:10,450 --> 00:35:12,860
U dan huwa biss minħabba l-
id-deċiżjonijiet rotta dinamiċi

768
00:35:12,860 --> 00:35:14,650
li dawn il-kompjuters qed jagħmlu.

769
00:35:14,650 --> 00:35:18,930
>> Issa biss għall-gost, it-tim tal-produzzjoni
mirqum waħda minn dawn il-videos għalina

770
00:35:18,930 --> 00:35:20,807
li jkun biss ftit aktar konċiż.

771
00:35:20,807 --> 00:35:23,640
Iżda biex tagħtina sens ta 'malajr here--
u nistgħu tħalli l-dwal on--

772
00:35:23,640 --> 00:35:32,363
dwar kemm kemm cabling huwa
fatt qed iġorr kollha tad-data tagħna.

773
00:35:32,363 --> 00:35:33,029
[Daqq video]

774
00:35:33,029 --> 00:35:36,023
[Daqq tal-mużika]

775
00:35:36,023 --> 00:36:31,911

776
00:36:31,911 --> 00:36:32,777
[END Daqq]

777
00:36:32,777 --> 00:36:35,860
DAVID J. Malan: Kollha videos netwerking
jkollhom mużika jagħmlu ħoss jibred apparentament.

778
00:36:35,860 --> 00:36:38,084
Allura dak li tikseb biss
sens ta 'kemm kemm għandek

779
00:36:38,084 --> 00:36:39,500
ilu għaddej taħt il-barnuża.

780
00:36:39,500 --> 00:36:41,355
>> Imma ejja nħarsu lejn
f'livell kemmxejn anqas issa

781
00:36:41,355 --> 00:36:44,150
lejn dak id-data hija attwalment
traversat dawk il-linji,

782
00:36:44,150 --> 00:36:46,720
u anki jmorru wirelessly
fil-kamra bħal din.

783
00:36:46,720 --> 00:36:49,580
>> Għalhekk jirriżulta li meta inti titlob
web page, jew ibgħat e-mail,

784
00:36:49,580 --> 00:36:53,670
jew jirċievu web page, jew e-mail, jew
messaġġ Gchat, jew messaġġ Facebook,

785
00:36:53,670 --> 00:36:57,800
jew bħalhom, li huwa mhux biss wieħed
blokki kbar ta 'bits li jirriżultaw wirelessly

786
00:36:57,800 --> 00:37:00,600
fl-arja jew
elettronikament fuq wire.

787
00:37:00,600 --> 00:37:03,680
Pjuttost, din it-talba jew
rispons huwa ġeneralment

788
00:37:03,680 --> 00:37:05,810
chunked up f'biċċiet separati.

789
00:37:05,810 --> 00:37:08,880
>> Allura fi kliem ieħor, meta inti jkollhom
jitlob li jagħmlu ta 'kompjuter ieħor,

790
00:37:08,880 --> 00:37:10,980
jew ikollok lura rispons
minn computer-- ieħor

791
00:37:10,980 --> 00:37:15,800
bħal jissoponi, per eżempju, jekk
unfamiliar-- kif wisq nies

792
00:37:15,800 --> 00:37:18,400
jidhru li huma dawn days--
jekk familjari mal this--

793
00:37:18,400 --> 00:37:20,200
ma dan fellow-- dan sħabi.

794
00:37:20,200 --> 00:37:23,950
Allura jissoponi dan huwa messaġġ li
I trid tibgħat lil xi ħadd fid-dahar.

795
00:37:23,950 --> 00:37:28,930
Min fl-dahar ħafna tixtieq
jirċievu stampa ta 'Rick Astley llum?

796
00:37:28,930 --> 00:37:29,805
OK, x'hemm isem tiegħek?

797
00:37:29,805 --> 00:37:30,590
>> UDJENZA: Cole.

798
00:37:30,590 --> 00:37:31,306
>> DAVID J. Malan: X'inhu dan?

799
00:37:31,306 --> 00:37:31,672
>> UDJENZA: Cole.

800
00:37:31,672 --> 00:37:32,040
>> DAVID J. Malan: Holt?

801
00:37:32,040 --> 00:37:32,540
H-O?

802
00:37:32,540 --> 00:37:33,711
UDJENZA: C-O-L-E.

803
00:37:33,711 --> 00:37:34,960
DAVID J. Malan: C-O-L-E, Cole.

804
00:37:34,960 --> 00:37:35,520
Jiddispjacini.

805
00:37:35,520 --> 00:37:36,430
C-O-L-E.

806
00:37:36,430 --> 00:37:36,930
Kull dritt.

807
00:37:36,930 --> 00:37:40,990
Mela jekk jien tixtieq li tibgħat Cole dan
stampa hawn, inti taf dan

808
00:37:40,990 --> 00:37:42,410
huwa tip ta 'stampa kbira, id-dritt?

809
00:37:42,410 --> 00:37:44,472
Dan jista 'jkun xi ftit
kilobytes, megabytes ftit,

810
00:37:44,472 --> 00:37:45,930
speċjalment jekk huwa riżoluzzjoni għolja.

811
00:37:45,930 --> 00:37:48,660
U jien ma verament jixtiequ jieqfu
kulħadd milli jużaw l-internet

812
00:37:48,660 --> 00:37:50,680
biss filwaqt nibgħat dan verament
big, stampa ta 'kwalità għolja

813
00:37:50,680 --> 00:37:52,138
tal Rick Astley matul il-kamra.

814
00:37:52,138 --> 00:37:55,310
Nixtieq data tiegħek lil jkomplu
travers-netwerk u l-Wi-Fi

815
00:37:55,310 --> 00:37:56,100
kif ukoll.

816
00:37:56,100 --> 00:38:00,100
>> U għalhekk jagħmel sense-- u dan
jiġi rkuprat b'mod elettroniku,

817
00:38:00,100 --> 00:38:01,780
mhux tant fid-dinja reali.

818
00:38:01,780 --> 00:38:04,904
Attwalment, dan se jkollu multipli
tifsiriet jekk tieħu awdjo tiegħi out.

819
00:38:04,904 --> 00:38:08,360
Mela jekk jien tiċrita dan
il-half bħal dan hawn,

820
00:38:08,360 --> 00:38:11,912
dan issa jistgħu jivvjaġġaw l
internet b'mod aktar effiċjenti,

821
00:38:11,912 --> 00:38:13,120
għaliex dan huwa biċċa iżgħar.

822
00:38:13,120 --> 00:38:16,780
Allura bi probabbiltà aktar baxx huwa se
li jikkonfliġġu ma 'traffiku xi ħadd ieħor

823
00:38:16,780 --> 00:38:17,650
fuq l-internet.

824
00:38:17,650 --> 00:38:21,240
>> U iva, liema kompjuter tiegħek tabilħaqq ma
meta inti tixtieq li jibgħat messaġġ lill Cole

825
00:38:21,240 --> 00:38:24,917
huwa biċċiet up messaġġ bħal dan fis
biċċiet iżgħar, frammenti biex ngħidu hekk.

826
00:38:24,917 --> 00:38:28,000
U allura ipoġġihom ġewwa ta 'dak
aħna ser sejħa tip ta 'pakketti virtwali.

827
00:38:28,000 --> 00:38:29,620
>> So I jkollhom erba 'pakketti karta hawn.

828
00:38:29,620 --> 00:38:32,690
U stajt pre-nnumerati minnhom,
wieħed, tnejn, tlieta, u erbgħa.

829
00:38:32,690 --> 00:38:35,800
U dak li jien ser tagħmel fuq il-front
ta 'dan, bħad posta normali,

830
00:38:35,800 --> 00:38:38,000
huwa Jien ser tpoġġi isem Cole hemmhekk.

831
00:38:38,000 --> 00:38:41,270
U mbagħad fil-quċċata, jien
se timplimenta l-isem tiegħi hemm,

832
00:38:41,270 --> 00:38:44,995
David, b'tali mod li l-ewwel tali pakkett
Jien tibgħat hemmhekk fuq l-internet

833
00:38:44,995 --> 00:38:47,620
jistenna ftit xi ħaġa bħal
dan, il-karatteristiċi ewlenin

834
00:38:47,620 --> 00:38:50,830
li huma li hija għandha
biex jindirizzaw, a mill-indirizz,

835
00:38:50,830 --> 00:38:52,670
u wkoll numru, hekk
li din nisperaw

836
00:38:52,670 --> 00:38:55,680
huwa biżżejjed informazzjoni għall
Cole li jirrikostitwixxu dan il-messaġġ.

837
00:38:55,680 --> 00:38:58,820
>> So let me jagħmlu l-istess hawn, il-
istess hawn, u l-istess hawn,

838
00:38:58,820 --> 00:39:01,310
kitba isimha fil-
Biex qasam fuq kull wieħed minnhom.

839
00:39:01,310 --> 00:39:04,240
U mbagħad ejja imorru quddiem u
tpoġġi dawn l-istampi ġewwa.

840
00:39:04,240 --> 00:39:06,540
>> Allura hawnhekk huwa pakkett wieħed
li lesta li tmur.

841
00:39:06,540 --> 00:39:09,780
Hawnhekk huwa packet ieħor
li lesta li tmur.

842
00:39:09,780 --> 00:39:14,100
Hawnhekk huwa t-tielet pakkett
li lesta li tmur.

843
00:39:14,100 --> 00:39:16,870
U hawn huwa r-raba
packet li lesta li tmur.

844
00:39:16,870 --> 00:39:19,849
>> U issa x'hemm interessanti dwar
kif l-internet f'xogħlijiet realtà

845
00:39:19,849 --> 00:39:22,140
hija li anke jekk stajt ltqajna
erba pakketti, li kollha

846
00:39:22,140 --> 00:39:24,730
huma destinati għall-istess
post, dawn mhux qed neċessarjament

847
00:39:24,730 --> 00:39:26,870
ser travers l-istess rotta.

848
00:39:26,870 --> 00:39:32,070
U hekk anki jekk I jista idejn dawn
pakketti sa l-eqreb router

849
00:39:32,070 --> 00:39:36,660
ejja ngħidu, jekk inti tixtieq li
jibgħathom kull mod, ejja naraw

850
00:39:36,660 --> 00:39:40,706
x'inhu dak li attwalment jiġri, l-għan ta '
li huwa li twassalhom finalment lill Cole.

851
00:39:40,706 --> 00:39:44,850

852
00:39:44,850 --> 00:39:48,770
U fil-fatt, dawn qed diġà ma
neċessarjament tieħu l-istess direzzjoni.

853
00:39:48,770 --> 00:39:50,510
U li l-multa.

854
00:39:50,510 --> 00:39:52,480
Dan huwa ftit skomdi
u stil Oprah llum.

855
00:39:52,480 --> 00:39:56,540
>> U issa let me deliberatament
jieħdu dik lura waħda.

856
00:39:56,540 --> 00:40:00,196
U issa Cole, jekk inti tixtieq li
reassemble dan bħala l-aħjar tista '.

857
00:40:00,196 --> 00:40:06,610

858
00:40:06,610 --> 00:40:10,180
Of course, nistgħu kollha raden dak
il-konklużjoni hawn se tkun.

859
00:40:10,180 --> 00:40:12,600
Inti qed tmur biex ikollhom 04/03 ta
Rick Astley fi ftit mument.

860
00:40:12,600 --> 00:40:15,920

861
00:40:15,920 --> 00:40:19,291
U dak għalkemm huwa l-
implikazzjoni ta 'dak?

862
00:40:19,291 --> 00:40:20,540
Inti tixtieq li jippruvaw li jżommu it up?

863
00:40:20,540 --> 00:40:23,540
We do jkollhom camera waħda
osservat fi inti jekk inti tixtieq

864
00:40:23,540 --> 00:40:26,226
li joħolqu ma 'Rick Astley hawn.

865
00:40:26,226 --> 00:40:28,610

866
00:40:28,610 --> 00:40:29,510
Hemm immorru.

867
00:40:29,510 --> 00:40:30,410
Sabiħ.

868
00:40:30,410 --> 00:40:33,230
>> Imma inti jidhru li huma nieqsa
framment ta 'Rick Astley.

869
00:40:33,230 --> 00:40:37,015
Għalhekk jirriżulta li l-internet
ġeneralment mmexxija mill mhux biss IP,

870
00:40:37,015 --> 00:40:39,890
iżda fil-fatt aħna jinstemgħu fil-ħafna
bidu ta 'lecture f'dak video--

871
00:40:39,890 --> 00:40:42,473
u inti stajt probabbilment jidhru dan
akronimu aktar often-- dak li verament

872
00:40:42,473 --> 00:40:44,360
huwa l-protokoll inti għandek tendenza li tisma 'dwar?

873
00:40:44,360 --> 00:40:45,120
>> UDJENZA: TCP / IP.

874
00:40:45,120 --> 00:40:48,090
>> DAVID J. Malan: TCP / IP,
li huwa biss kombinazzjoni

875
00:40:48,090 --> 00:40:49,940
ta 'żewġ protokolli, wieħed imsejjaħ IP.

876
00:40:49,940 --> 00:40:52,640
Li għal darb'oħra, huwa biss is-sett
ta 'konvenzjonijiet li permezz tagħhom aħna

877
00:40:52,640 --> 00:40:54,740
jindirizzaw kull kompjuter fl-internet.

878
00:40:54,740 --> 00:40:56,930
U mbagħad TCP, li
iservi skop ieħor.

879
00:40:56,930 --> 00:41:00,110
>> TCP huwa protokoll li inti
tipikament jużaw flimkien

880
00:41:00,110 --> 00:41:04,410
ma IP, li fost oħrajn
affarijiet, garanziji kunsinna.

881
00:41:04,410 --> 00:41:08,860
Fil-fatt, TCP huwa l-protokoll li
tinnota li wieħed mill-pakketti

882
00:41:08,860 --> 00:41:10,930
apparentament ma jiksbu biex
Cole, għaliex huwa jidher

883
00:41:10,930 --> 00:41:12,830
li jkun in-numru erbgħa neqsin minn erbgħa.

884
00:41:12,830 --> 00:41:16,530
U għalhekk dak TCP, protokoll
ma, huwa jgħidlekx Cole,

885
00:41:16,530 --> 00:41:19,850
ħej Cole, jekk inti tirċievi biss
tlieta minn erba 'pakketti,

886
00:41:19,850 --> 00:41:22,600
tell me liema waħda inti
huma neqsin, essenzjalment,

887
00:41:22,600 --> 00:41:25,570
u mbagħad iskop tiegħi fil-ħajja
għandu jkun li terġa 'titrażmetti lura din.

888
00:41:25,570 --> 00:41:28,580
>> U hekk jekk I wisq, il-
mittent, qed jużaw TCP,

889
00:41:28,580 --> 00:41:31,810
I għandhom imbagħad joħloq packet-- ġdida
ma dan mkemmxa here-- wieħed

890
00:41:31,810 --> 00:41:35,980
jerġa jxandar biss din il-biċċa ta '
tagħha, b'mod li finalment Cole għandha

891
00:41:35,980 --> 00:41:38,280
tifkira kompluta, jekk xejn.

892
00:41:38,280 --> 00:41:43,000
Iżda b'mod li finalment d-data fil-fatt
gets lejn id-destinazzjoni korretta tagħha.

893
00:41:43,000 --> 00:41:48,020
>> Iżda sfortunatament, kitba isem Cole
fuq quddiem mhuwiex biżżejjed, fih innifsu.

894
00:41:48,020 --> 00:41:50,270
U tassew, jien ma jiktbu
Isem Cole, iżda probabbilment

895
00:41:50,270 --> 00:41:51,655
indirizz IP tiegħu fuq l-envelop.

896
00:41:51,655 --> 00:41:52,780
U jien ma se jikteb David.

897
00:41:52,780 --> 00:41:56,550
I d jiktbu indirizz IP tiegħi fuq l-envelop
sabiex l-kompjuters tista 'attwalment

898
00:41:56,550 --> 00:41:57,999
jikkomunikaw quddiem u lura.

899
00:41:57,999 --> 00:42:00,540
Iżda jirriżulta li l-kompjuters
tista 'tagħmel aktar minn mod iservu up

900
00:42:00,540 --> 00:42:01,900
stampi ta 'Rick Astley.

901
00:42:01,900 --> 00:42:05,340
Huma jistgħu wkoll resend u
tirċievi emails, chat messaġġi.

902
00:42:05,340 --> 00:42:09,780
Huma jistgħu jagħmlu affarijiet simili file transfers,
u kull numru ta 'għodod oħra

903
00:42:09,780 --> 00:42:12,330
inti użu fuq l-internet,
servers jistgħu jagħmlu dawn il-jiem.

904
00:42:12,330 --> 00:42:15,300
>> U biss minħabba li kumpanija,
jew skola, jew persuna

905
00:42:15,300 --> 00:42:19,420
trid ikollha web server, u
server email, u chat server,

906
00:42:19,420 --> 00:42:21,420
ma jfissirx li għandek bżonn tliet kompjuters.

907
00:42:21,420 --> 00:42:26,200
Inti jista 'jkollhom biss kompjuter running wieħed
servizzi multipli, biex ngħidu hekk.

908
00:42:26,200 --> 00:42:29,190
>> U hekk meta Cole jirċievi
messaġġ bħal dik, kif

909
00:42:29,190 --> 00:42:32,940
ma kompjuter tiegħu jaf jekk
juru li stampa fil-browser tiegħu,

910
00:42:32,940 --> 00:42:37,730
jew Gchat, jew Facebook Messenger,
jew fi kwalunkwe numru ta 'għodod oħra?

911
00:42:37,730 --> 00:42:40,430
>> Għalhekk jirriżulta wkoll fuq dak
kif pakkett huwa biċċa addizzjonali

912
00:42:40,430 --> 00:42:43,070
ta 'informazzjoni magħrufa bħala numru port.

913
00:42:43,070 --> 00:42:45,240
U numru port huwa
biss numru tabilħaqq,

914
00:42:45,240 --> 00:42:48,342
iżda unikament jidentifika mhux
il-kompjuter, iżda s-servizz.

915
00:42:48,342 --> 00:42:49,550
U hemm għenieqed ta 'dawn.

916
00:42:49,550 --> 00:42:51,258
Għalhekk jirriżulta li
fid-dinja, bnedmin

917
00:42:51,258 --> 00:42:57,095
iddeċidejt fuq ftit bħal
konvenzjonijiet, li wħud minnhom huma dawn.

918
00:42:57,095 --> 00:42:59,220
Allura hemm xi ħaġa imsejjaħ
File Transfer Protocol.

919
00:42:59,220 --> 00:42:59,870
Huwa pretty datata.

920
00:42:59,870 --> 00:43:00,970
Huwa kompletament mhux sikur.

921
00:43:00,970 --> 00:43:02,320
Ħafna nies għadhom jużaw dan.

922
00:43:02,320 --> 00:43:04,240
U juża numru tal-port 21.

923
00:43:04,240 --> 00:43:07,250
Fi kliem ieħor, jekk
tibgħat fajl permezz ta 'FTP,

924
00:43:07,250 --> 00:43:10,570
il-pakkett m'għandux ikollu biss l
jibgħat u min jirċievi l-indirizz IP,

925
00:43:10,570 --> 00:43:14,020
ikollha wkoll l-għadd 21 sabiex
il-kompjuter li jirċievi jaf oh, din

926
00:43:14,020 --> 00:43:17,280
huwa fajl, mhux email
jew messaġġ chat.

927
00:43:17,280 --> 00:43:19,016
>> 25 huwa SMTP.

928
00:43:19,016 --> 00:43:20,516
Kemm inti qatt jintużaw SMTP?

929
00:43:20,516 --> 00:43:22,850

930
00:43:22,850 --> 00:43:23,380
Ħażin.

931
00:43:23,380 --> 00:43:24,490
Kważi kollha inti għandek.

932
00:43:24,490 --> 00:43:28,730
Jekk inti stajt qatt jintużaw email, inti ħadthom użati
SMTP, protokoll ta 'trasferiment sempliċi mail,

933
00:43:28,730 --> 00:43:32,300
li huwa biss mod fancy ta 'tgħid,
dan huwa t-tip ta 'kompjuter jew servizz

934
00:43:32,300 --> 00:43:34,600
li jibgħat barra email tiegħek.

935
00:43:34,600 --> 00:43:38,780
>> U jekk inti stajt qatt rat akronimi bħal
POP, jew IMAP, u hemm ftit oħrajn,

936
00:43:38,780 --> 00:43:40,670
dawn huma biex jirċievu
email, tipikament.

937
00:43:40,670 --> 00:43:42,650
Li sempliċiment ifisser li huwa
servizz differenti.

938
00:43:42,650 --> 00:43:45,850
Huwa software li xi ħadd
kiteb li jibgħat jew jisma

939
00:43:45,850 --> 00:43:48,880
fuq numru speċifiku port hekk
li ma jħawwadhomx emails

940
00:43:48,880 --> 00:43:50,360
ma 'xi tip ieħor ta' data.

941
00:43:50,360 --> 00:43:55,500
>> Issa l-web huwa HTTP, li huwa
numru 80, u wkoll port 443.

942
00:43:55,500 --> 00:43:57,590
U fil-fatt, anki jekk
aħna bnedmin fortunatament

943
00:43:57,590 --> 00:43:59,610
ma għandekx tagħmel dan,
kwalunkwe ħin li żżur

944
00:43:59,610 --> 00:44:05,810
websajt bħal
http://www.yale.edu, il-browser

945
00:44:05,810 --> 00:44:07,790
huwa sempliċement tip ta '
utli fil li huwa

946
00:44:07,790 --> 00:44:10,970
jekk wieħed jassumi li inti tixtieq port numerika 80.

947
00:44:10,970 --> 00:44:15,710
Aħna diġà jafu li DNS tistax figura
dak l-indirizz IP huwa ta 'www.yale.edu.

948
00:44:15,710 --> 00:44:17,970
Iżda l-kompjuter hija biss
ser jiddeduċu li inti

949
00:44:17,970 --> 00:44:21,560
tixtieq port 80 għaliex inti qed tuża
Chrome, jew IE, jew xi browser oħra.

950
00:44:21,560 --> 00:44:24,930
Imma I jistgħu teknikament jagħmlu kolon 80.

951
00:44:24,930 --> 00:44:28,520
U mbagħad I tista 'tgħid b'mod espliċitu
browser tiegħi, tibgħat pakkett jew aktar

952
00:44:28,520 --> 00:44:32,080
ta 'informazzjoni lill www.yale.edu
jitlob home page lum.

953
00:44:32,080 --> 00:44:36,070
Iżda speċifikament, l-indirizz
li PI Yale fiż port 80

954
00:44:36,070 --> 00:44:39,190
I hekk li fil-fatt tikseb
back web server Yale.

955
00:44:39,190 --> 00:44:42,229
>> Issa immedjatament tisparixxi
minħabba browsers biss

956
00:44:42,229 --> 00:44:44,020
tiddeċiedi li aħna ma
jeħtieġ li jħawdu bnedmin

957
00:44:44,020 --> 00:44:46,810
billi għadhom aktar arcane
informazzjoni bħal kolon 80.

958
00:44:46,810 --> 00:44:50,640
U franchement, browsers
bħal Chrome ma anki

959
00:44:50,640 --> 00:44:55,464
nuruk HTTP aktar, jew il-kolon, jew
l mmejla mmejla, jew il mmejla batuta,

960
00:44:55,464 --> 00:44:58,380
f'ċertu sens għaliex qed jippruvaw
biex tagħmel affarijiet eħfef għall-utenti.

961
00:44:58,380 --> 00:45:01,080
Fis-sens ieħor, huwa biss tip
ta 'esperjenza utent thing--

962
00:45:01,080 --> 00:45:02,720
ejja jeħles ta 'xi wħud mill-eki mhux mixtieqa.

963
00:45:02,720 --> 00:45:05,405
Iżda huwa ħabi xi wħud
dawn id-dettalji bażiċi.

964
00:45:05,405 --> 00:45:09,360
>> U fil-fatt, ħadd minna
probabbilment qatt tip http aktar.

965
00:45:09,360 --> 00:45:12,060
Inti biss tip xi ħaġa
bħal www.harvard.edu.

966
00:45:12,060 --> 00:45:15,310
U għal darb'oħra, tiddeduċi Chrome
li inti tixtieq HTTP.

967
00:45:15,310 --> 00:45:18,970
Iżda hemm protokolli oħra
li nistgħu ċertament tkun qed tuża.

968
00:45:18,970 --> 00:45:24,480
>> Hekk meta wieħed iqis dan kollu, jekk inti issa sort
tal mqiegħda fis-hekk imsejħa hat inġinerija,

969
00:45:24,480 --> 00:45:27,417
kif do affarijiet imsejħa firewalls xogħol?

970
00:45:27,417 --> 00:45:29,750
Allura int probabilment ġeneralment
familjari mal-firewall,

971
00:45:29,750 --> 00:45:30,990
mhux tant fis-sens fiżiku.

972
00:45:30,990 --> 00:45:32,470
Allura lura fil-ġurnata,
u għadu sal-lum,

973
00:45:32,470 --> 00:45:35,430
jekk inti ħadthom ltqajna bħal malls strixxa għall
eżempju li għandhom ħafna ta 'ħwienet,

974
00:45:35,430 --> 00:45:38,500
ġeneralment l-ħitan fiż bejn
ħwienet individwali jew ħwienet

975
00:45:38,500 --> 00:45:43,180
huma firewalls fis-sens li
huma għandhom insulazzjoni speċjali

976
00:45:43,180 --> 00:45:45,310
b'tali mod li jekk nar
tfaqqa fil-ħanut wieħed,

977
00:45:45,310 --> 00:45:48,210
għaliex mhux neċessarjament
mifruxa fil-ħanut bieb li jmiss.

978
00:45:48,210 --> 00:45:51,710
>> Id-dinja tal-kompjuter għandu wkoll firewalls
li tagħmel xi ħaġa differenti.

979
00:45:51,710 --> 00:45:52,798
Xi jfisser Fireball do?

980
00:45:52,798 --> 00:45:53,298
Yeah?

981
00:45:53,298 --> 00:45:55,290
>> UDJENZA: Bażikament
huma maqtugħa konnessjoni

982
00:45:55,290 --> 00:45:59,493
jekk dawn jiltaqgħu xi ħaġa
bħal, per eżempju,

983
00:45:59,493 --> 00:46:01,361
huma għandhom numru ta 'dikjarazzjonijiet id.

984
00:46:01,361 --> 00:46:04,340
U jekk jiġri xi ħaġa,
huma maqtugħin il-konnessjoni.

985
00:46:04,340 --> 00:46:07,570
Bħal jekk dan l-attakk malizzjużi
[Inaudible]-kompjuter tiegħek, or--

986
00:46:07,570 --> 00:46:08,630
>> DAVID J. Malan: tajba OK.

987
00:46:08,630 --> 00:46:11,220
Yeah, u fil-fatt int
anki jmorru ftit farther

988
00:46:11,220 --> 00:46:14,590
fid-deskrizzjoni xi ħaġa li tista 'tkun
imsejħa sistema ta 'skoperta intrużjoni,

989
00:46:14,590 --> 00:46:18,305
jew IDS-qasir, fejn inti
attwalment jkollhom regoli definiti.

990
00:46:18,305 --> 00:46:22,140
U jekk inti tibda tara suspettużi
imġieba, inti tipprova ttemm lilha.

991
00:46:22,140 --> 00:46:24,250
>> U firewall, franchement,
f'livell netwerking,

992
00:46:24,250 --> 00:46:26,821
hija saħansitra dumber u aktar sempliċi
minn dan, ġeneralment.

993
00:46:26,821 --> 00:46:29,070
U hemm tipi differenti
ta 'firewalls fid-dinja.

994
00:46:29,070 --> 00:46:31,569
Iżda dawk li joperaw fil
il-livell aħna qed jitkellem today--

995
00:46:31,569 --> 00:46:35,330
IP u TCP-- jaħdmu anke
iktar sempliċement.

996
00:46:35,330 --> 00:46:39,180
>> Per eżempju, jekk inti kienu sistema Yale
amministraturi, jew is-sistema Harvard

997
00:46:39,180 --> 00:46:42,020
amministraturi, jew xi Big
Brother f'xi kumpanija,

998
00:46:42,020 --> 00:46:45,040
u int riedu biex jipprevjenu kollha tiegħek
studenti jew l-impjegati tiegħek

999
00:46:45,040 --> 00:46:47,619
milli jmorru facebook.com,
kull ma għandek tagħmel

1000
00:46:47,619 --> 00:46:50,160
hu li tagħmel żgur li kollha tagħhom
traffiku tan-network, l-ewwel nett,

1001
00:46:50,160 --> 00:46:51,850
tmur permezz ta 'apparat speċjali.

1002
00:46:51,850 --> 00:46:53,030
Ejja sejħa hija ta 'firewall.

1003
00:46:53,030 --> 00:46:54,910
>> U li l-multa, minħabba
inti tista 'tagħmel router tiegħek

1004
00:46:54,910 --> 00:46:57,618
l-istess ħaġa bħala firewall jekk
inti tpoġġi l-istess tip ta 'software

1005
00:46:57,618 --> 00:46:58,940
fuq l-istess magna.

1006
00:46:58,940 --> 00:47:01,780
Mela jekk il-istudenti tiegħek
jew impjegati traffiku

1007
00:47:01,780 --> 00:47:04,450
huwa għaddej permezz ta 'dan
firewall ċentrali, kif

1008
00:47:04,450 --> 00:47:08,540
kieku aħna blokk nies milli jmorru
li facebook.com, per eżempju?

1009
00:47:08,540 --> 00:47:10,780
Xi jkun is-sistema
amministratur għandek tagħmel?

1010
00:47:10,780 --> 00:47:11,370
Ħaddieħor?

1011
00:47:11,370 --> 00:47:12,911
Ejja nippruvaw li jmorru madwar.

1012
00:47:12,911 --> 00:47:15,074
>> UDJENZA: [inaudible]

1013
00:47:15,074 --> 00:47:16,365
DAVID J. Malan: Say li għal darb'oħra?

1014
00:47:16,365 --> 00:47:19,215
UDJENZA: Għandu biss tikseb
maqbuda ġewwa s-sistema.

1015
00:47:19,215 --> 00:47:22,487
Allura biss jitqiegħed Facebook fis 127.0.0--

1016
00:47:22,487 --> 00:47:23,820
DAVID J. Malan: Oh, interessanti.

1017
00:47:23,820 --> 00:47:27,290
Allura inti tista 'attwalment mbagħad
Hack sistema DNS tiegħek.

1018
00:47:27,290 --> 00:47:31,180
Dan huwa tabilħaqq mod inti tista 'tagħmel dan
li bih kwalunkwe ħin student Yale jiġbed

1019
00:47:31,180 --> 00:47:34,670
up www.facebook.com, kollha
minna hawn illum fuq il-kampus

1020
00:47:34,670 --> 00:47:38,590
qed jużaw server DNS Yale, il
minħabba server DHCP Yale ta lil magħna

1021
00:47:38,590 --> 00:47:39,580
dak l-indirizz.

1022
00:47:39,580 --> 00:47:42,490
Allura yeah, inti tista tip ta '
break affarijiet jew konvenzjoni break

1023
00:47:42,490 --> 00:47:49,190
bi ftit qal, yeah,
indirizz facebook.com huwa falz,

1024
00:47:49,190 --> 00:47:52,530
huwa 1.2.3.4, li huwa
mhux attwalment leġittimu.

1025
00:47:52,530 --> 00:47:53,930
Jew forsi huwa 278.

1026
00:47:53,930 --> 00:47:57,460
ikun x'ikun kien fil-programm tat-TV a
mument ilu sabiex l-ebda wieħed minna

1027
00:47:57,460 --> 00:47:59,176
jistgħu attwalment żjara facebook.com.

1028
00:47:59,176 --> 00:48:00,590
>> Allura jissoponi Yale ma dak.

1029
00:48:00,590 --> 00:48:03,336
Ejja ngħidu Yale riedu jżommu
inti out ta 'facebook.com.

1030
00:48:03,336 --> 00:48:05,700
U għalhekk, huma
biddel il-settings DNS

1031
00:48:05,700 --> 00:48:08,812
nagħtikom IP fittizji
jindirizza għall facebook.com.

1032
00:48:08,812 --> 00:48:10,616
Kif inti twieġeb?

1033
00:48:10,616 --> 00:48:12,990
Teknikament, not-- oh, issa
kulħadd jixtieq li jipparteċipaw.

1034
00:48:12,990 --> 00:48:13,490
OK, yeah.

1035
00:48:13,490 --> 00:48:16,190
UDJENZA: Inti biss tip fil-
indirizz IP attwali ta 'Facebook.

1036
00:48:16,190 --> 00:48:16,710
>> DAVID J. Malan: OK, tajba.

1037
00:48:16,710 --> 00:48:19,350
Allura nistgħu biss tip fil-
indirizz IP attwali ta 'Facebook,

1038
00:48:19,350 --> 00:48:21,090
ferm simili I did mal-website Yale.

1039
00:48:21,090 --> 00:48:24,636
U jekk il-server Facebook huwa kkonfigurat
biex issostni dik, din għandha tabilħaqq jaħdmu.

1040
00:48:24,636 --> 00:48:26,510
Huwa uġigħ minuri
l-għonq, għaliex issa aħna

1041
00:48:26,510 --> 00:48:30,220
għandek tiftakar xi każwali
Valur 32-bit, iżda li jistgħu jaħdmu.

1042
00:48:30,220 --> 00:48:31,622
X'aktar jista inti tagħmel?

1043
00:48:31,622 --> 00:48:32,121
Yeah.

1044
00:48:32,121 --> 00:48:35,117
>> UDJENZA: Inti tista 'tbiddel
dawk settings [inaudible].

1045
00:48:35,117 --> 00:48:37,700
DAVID J. Malan: Yeah, inti tista '
saħansitra l-bidla settings DNS tiegħek.

1046
00:48:37,700 --> 00:48:40,480
Allura fil-fatt dan huwa effettivament
pretty utli, franchement,

1047
00:48:40,480 --> 00:48:45,590
jekk int f'ajruport, jew jekk
int fil-kafetterija, jew xi ħaġa li

1048
00:48:45,590 --> 00:48:48,834
għandha internet titfarfar biha kultant
l-server DNS biss tieqaf mix-xogħol.

1049
00:48:48,834 --> 00:48:51,000
Għalhekk anki I kultant do
dan, mhux għall malizzjużi, I

1050
00:48:51,000 --> 00:48:52,750
jridu jużaw Facebook
skopijiet, imma verament

1051
00:48:52,750 --> 00:48:56,344
minħabba I jidhru li jkollhom netwerk
konnessjoni, iżda xejn qed taħdem.

1052
00:48:56,344 --> 00:48:58,260
U għalhekk wieħed mill-ewwel
affarijiet I try-- u inti

1053
00:48:58,260 --> 00:49:01,710
tista 'tagħmel dan fuq Windows too-- iżda
fuq Mac tiegħi, jekk immur Network.

1054
00:49:01,710 --> 00:49:03,330
U jien jagħżlu Wi-Fi konnessjoni tiegħi.

1055
00:49:03,330 --> 00:49:04,750
U mmur Avvanzata.

1056
00:49:04,750 --> 00:49:06,080
U mmur DNS.

1057
00:49:06,080 --> 00:49:08,260
Dawn huma t-tliet
Indirizzi IP li Yale

1058
00:49:08,260 --> 00:49:10,290
hija tagħti me għal tliet servers DNS.

1059
00:49:10,290 --> 00:49:14,110
L-iskop allura huwa għalija li jippruvaw xi
wieħed minn dawn li jsolvu l-indirizzi.

1060
00:49:14,110 --> 00:49:15,946
>> Imma nista 'jwarrab
dawn billi tagħmel plus.

1061
00:49:15,946 --> 00:49:18,333
U kull min jixtiequ li tipproponi server DNS?

1062
00:49:18,333 --> 00:49:19,120
>> UDJENZA: 8.8.8.8?

1063
00:49:19,120 --> 00:49:20,578
>> DAVID J. Malan: Oh, int aqwa.

1064
00:49:20,578 --> 00:49:21,650
Iva, 8.8.8.8.

1065
00:49:21,650 --> 00:49:26,170
Allura Google, bless qlub tagħhom,
xtara l-indirizz IP 8.8.8.8,

1066
00:49:26,170 --> 00:49:29,560
minħabba li tip ta 'qisu Gs
probabbilment, u huwa faċli li wieħed jiftakru.

1067
00:49:29,560 --> 00:49:34,820
Imma fil-fatt, issa għandi konfigurati tiegħi
kompjuter għall-użu server Google DNS.

1068
00:49:34,820 --> 00:49:38,050
>> Allura issa jekk mmur yale.edu,
huwa għadu sejjer jaħdem.

1069
00:49:38,050 --> 00:49:40,100
Imma jien ma jużawx l Yale
Servers DNS aktar.

1070
00:49:40,100 --> 00:49:44,430
U jekk immur facebook.com,
dawk kollha ħarsa ups

1071
00:49:44,430 --> 00:49:45,960
se jmorru permezz ta 'Google.

1072
00:49:45,960 --> 00:49:49,120
>> Allura fuq naħa waħda, stajt cleverly
evitati s-sistema lokali

1073
00:49:49,120 --> 00:49:51,810
amministraturi biss minn
jifhem kif xogħlijiet netwerking.

1074
00:49:51,810 --> 00:49:53,360
Imma jien tħallas prezz.

1075
00:49:53,360 --> 00:49:54,740
Xejn huwa b'xejn.

1076
00:49:54,740 --> 00:49:56,096
Liema kienu I biss rrinunzjaw?

1077
00:49:56,096 --> 00:50:00,180

1078
00:50:00,180 --> 00:50:02,250
Liema kienu I biss rrinunzjaw?

1079
00:50:02,250 --> 00:50:06,090
In-nies kollha minnkom għaqlija li għandhom
kienu jużaw 8.8.8.8, għaliex dan huwa jibred

1080
00:50:06,090 --> 00:50:10,440
jew issolvi problemi, liema jkollhom
inti qed tagħmel dan il-ħin?

1081
00:50:10,440 --> 00:50:11,910
>> UDJENZA: Jivvjaġġaw farther?

1082
00:50:11,910 --> 00:50:15,201
>> DAVID J. Malan: Forsi jivvjaġġaw farther,
minħabba Google probabbilment mhux daqshekk

1083
00:50:15,201 --> 00:50:16,770
qrib il-server fl-triq.

1084
00:50:16,770 --> 00:50:18,420
Iżda aktar worrisomely.

1085
00:50:18,420 --> 00:50:18,920
Yeah?

1086
00:50:18,920 --> 00:50:20,940
>> UDJENZA: Allura issa Google
jaf fejn int ser.

1087
00:50:20,940 --> 00:50:23,856
>> DAVID J. Malan: Google jaf litteralment
kull website inti qed iżżur,

1088
00:50:23,856 --> 00:50:26,080
għaliex inti litteralment
talbithom, ħej Google,

1089
00:50:26,080 --> 00:50:28,360
inti tista 'tittraduċi yale.edu għalija?

1090
00:50:28,360 --> 00:50:32,430
Jew ħej Google, inti tista 'tittraduċi
dan l-indirizz websajt oħra għalija

1091
00:50:32,430 --> 00:50:33,334
fi indirizz IP.

1092
00:50:33,334 --> 00:50:35,750
U hekk they're-- għandi l-ebda
idea dak li qed nitkellmu.

1093
00:50:35,750 --> 00:50:38,080
U sabiex ikunu jafu kollox dwarek.

1094
00:50:38,080 --> 00:50:42,180
Allura jirrealizzaw li dan huwa servizz b'xejn
bi skop mill-perspettiva tagħhom

1095
00:50:42,180 --> 00:50:42,680
kif ukoll.

1096
00:50:42,680 --> 00:50:44,420
Iżda din tista 'ċertament
ikollok out ta jorbot.

1097
00:50:44,420 --> 00:50:46,380
>> Issa biss biex jiġu indirizzati ieħor
kwistjoni li spiss jitla '

1098
00:50:46,380 --> 00:50:48,640
fost l-istudenti, speċjalment
meta jivvjaġġaw internazzjonalment

1099
00:50:48,640 --> 00:50:50,765
f'ċerti pajjiżi bħall
Ċina, fejn hemm tabilħaqq

1100
00:50:50,765 --> 00:50:54,559
huwa Firewall Kbir taċ-Ċina permezz tagħha
il-gvern hemm blokki pjuttost

1101
00:50:54,559 --> 00:50:56,100
daqsxejn ta 'traffiku fuq livelli differenti.

1102
00:50:56,100 --> 00:50:58,141
Inti ma għandekx biss
jimblukkaw it-traffiku fuq il-livell

1103
00:50:58,141 --> 00:51:01,240
aħna qed jitkellem hawn, DNS jew mod ieħor,
inti tista 'jimblokka dan f'livelli oħra.

1104
00:51:01,240 --> 00:51:04,030
>> U fil-fatt, biss biex
tkun ċara, firewall

1105
00:51:04,030 --> 00:51:08,400
jistgħu joperaw aktar sempliċement milli sempliċement
li l-amministraturi tas-sistema bidla

1106
00:51:08,400 --> 00:51:09,500
Settings DNS.

1107
00:51:09,500 --> 00:51:12,920
A firewall, mezz bejn
magħna u l-bqija tad-dinja,

1108
00:51:12,920 --> 00:51:16,850
tista 'biss jimblokka kwalunkwe ħierġa
talbiet lill-indirizz IP

1109
00:51:16,850 --> 00:51:21,240
għall Facebook fuq port 80, jew
-indirizz IP għall harvard.edu,

1110
00:51:21,240 --> 00:51:22,580
jew l-indirizz IP ta 'xejn.

1111
00:51:22,580 --> 00:51:26,280
Allura firewall tista 'tħares lejn tiegħek
pakketti "indirizzi IP u saħansitra port

1112
00:51:26,280 --> 00:51:29,384
numri, u jekk Yale riedu,
din tista 'biss tieqaf lkoll

1113
00:51:29,384 --> 00:51:32,550
minn anki bl-użu FTP aktar, li kieku
probabbilment tkun ħaġa tajba għaliex

1114
00:51:32,550 --> 00:51:34,320
huwa tabilħaqq protokoll mhux sikur.

1115
00:51:34,320 --> 00:51:37,620
Yale tista anki jwaqqfu us milli
jżuru l-intier tal-web

1116
00:51:37,620 --> 00:51:42,632
biss billi jimblokka kollha port
traffiku fuq in-numru 80 kif ukoll.

1117
00:51:42,632 --> 00:51:43,840
Allura li jista 'jkun mod ieħor.

1118
00:51:43,840 --> 00:51:45,740
U hemm modi anki fancier kif ukoll.

1119
00:51:45,740 --> 00:51:47,770
>> Imma meta inti qed jivvjaġġaw
barra per eżempju,

1120
00:51:47,770 --> 00:51:50,740
jew jekk int fi kafetterija internet,
jew jekk int kullimkien fejn hemm

1121
00:51:50,740 --> 00:51:53,179
sadd jew theddid, dak li tista 'taghmel?

1122
00:51:53,179 --> 00:51:56,220
Ukoll, jekk inti tmur fl-triq biex
Starbucks jew tivvjaġġa f'ajruport,

1123
00:51:56,220 --> 00:51:58,780
ġeneralment inti tista 'sempliċement ħops
fuq il Wi-Fi billi jagħżlu

1124
00:51:58,780 --> 00:52:04,631
bħal, JFK Wi-Fi tal LaGuardia Wi-Fi,
jew Logan Ajruport Wi-Fi, jew dak li mhux.

1125
00:52:04,631 --> 00:52:05,880
U mhuwiex encrypted, id-dritt?

1126
00:52:05,880 --> 00:52:06,949
M'hemm l-ebda icon katnazz.

1127
00:52:06,949 --> 00:52:09,490
U int probabilment mhux imqanqla
għal username u password.

1128
00:52:09,490 --> 00:52:11,240
Int biss imqanqla
ma 'xi forma stupid

1129
00:52:11,240 --> 00:52:15,260
ngħid simili, I jaqblu li jużaw dan biss
għal 30 minuta, jew xi ħaġa bħal dik.

1130
00:52:15,260 --> 00:52:18,761
>> Iżda hemm ebda encryption bejn
inti u Starbucks Wi-Fi aċċess

1131
00:52:18,761 --> 00:52:20,760
punt, l-affarijiet ma
l-antenni fuq il-ħajt.

1132
00:52:20,760 --> 00:52:24,840
M'hemm l-ebda encryption bejnek
u Wi-Fi sinjali l-ajruport.

1133
00:52:24,840 --> 00:52:29,060
>> U għalhekk teknikament, dik il-persuna creepy
seduta sedili ftit isfel mill inti

1134
00:52:29,060 --> 00:52:31,970
fi Starbucks jew fl-ajruport
jista 'jkun, mas-softwer dritt,

1135
00:52:31,970 --> 00:52:35,164
jaraw kollha ta 'wireless tiegħek
traffiku fuq laptop tiegħu jew tagħha.

1136
00:52:35,164 --> 00:52:37,080
Mhuwiex diffiċli li
tpoġġi laptop fis x'hemm

1137
00:52:37,080 --> 00:52:39,880
imsejħa modalità promiscuous,
li kif tissuġġerixxi l-isem,

1138
00:52:39,880 --> 00:52:41,760
ifisser li int tip ta '
loose mar-regoli.

1139
00:52:41,760 --> 00:52:44,740
U hija biss jisma mhux biss
għat-traffiku maħsuba għal dan,

1140
00:52:44,740 --> 00:52:47,700
iżda wkoll biex kulħadd huwa
traffiku fil-firxa.

1141
00:52:47,700 --> 00:52:50,550
>> U minn dak loġika, dan jista 'jara
kollha tal-pakketti ta 'informazzjoni

1142
00:52:50,550 --> 00:52:51,360
int tirċievi.

1143
00:52:51,360 --> 00:52:53,510
U jekk dawn il-pakketti
mhumiex encrypted, inti

1144
00:52:53,510 --> 00:52:56,680
tpoġġi lilek innifsek f'riskju ta '
emails tiegħek, jew messaġġi tiegħek,

1145
00:52:56,680 --> 00:52:58,620
jew xi ħaġa oħra jkollna esposti.

1146
00:52:58,620 --> 00:53:01,220
>> Għalhekk anki jekk int ma barra
imma int biss fil Starbucks,

1147
00:53:01,220 --> 00:53:03,800
jew int fuq xi persuna każwali ta
Wi-Fi li mhux encrypted,

1148
00:53:03,800 --> 00:53:05,410
VPN hija ħaġa tajba.

1149
00:53:05,410 --> 00:53:07,410
A VPN huwa netwerk virtwali privat.

1150
00:53:07,410 --> 00:53:09,480
U huwa teknoloġija
li jippermettilek li jkollhom

1151
00:53:09,480 --> 00:53:14,560
kriptat, a connection-- scrambled
fancier minn Caesar jew Vigenere--

1152
00:53:14,560 --> 00:53:17,420
bejn laptop tiegħek, jew
telefon tiegħek, jew desktop tiegħek,

1153
00:53:17,420 --> 00:53:22,460
u server x'imkien ieħor, bħal
server fuq il-kampus Yale.

1154
00:53:22,460 --> 00:53:25,840
>> U jekk inti qed jivvjaġġaw abroad--
u fil-fatt, inti ssib dan fil-lukandi

1155
00:53:25,840 --> 00:53:26,560
il-ħin kollu.

1156
00:53:26,560 --> 00:53:28,580
U speċjalment fir jaspiraw
xjenzjati tal-kompjuter

1157
00:53:28,580 --> 00:53:32,090
fejn inti guys tista ', bħala geeks,
jridu jużaw portijiet oħrajn minn 80,

1158
00:53:32,090 --> 00:53:35,770
u portijiet minbarra 443-- u
fil-fatt għall-problema stabbiliti sitt,

1159
00:53:35,770 --> 00:53:39,280
se nkunu qed jilagħbu ma multipli
Portijiet TCP biss minn choice-- ħafna

1160
00:53:39,280 --> 00:53:42,940
ta 'lukandi, u ħwienet, u netwerks
biss blokk dak it-tip ta 'għalf

1161
00:53:42,940 --> 00:53:45,970
għaliex kemmxejn naively,
jew ignorantly, just think

1162
00:53:45,970 --> 00:53:48,010
li l-ebda wieħed jeħtieġ dawk il-portijiet oħra.

1163
00:53:48,010 --> 00:53:51,150
>> U hekk billi tuża VPN tista 'inti
jaħarbu dawk it-tipi ta 'restrizzjonijiet,

1164
00:53:51,150 --> 00:53:54,050
għaliex dak VPN ma huwa
din tippermetti li inti fil Starbucks,

1165
00:53:54,050 --> 00:53:58,630
jew l-ajruport, jew fi kwalunkwe post fid-dinja
li jgħaqqdu encryptedly li yale.edu,

1166
00:53:58,630 --> 00:54:02,950
għal xi server hawn fuq il-kampus,
u mbagħad mina, biex ngħidu hekk,

1167
00:54:02,950 --> 00:54:06,570
kollha ta 'traffiku tiegħek minn fejn
inti permezz Yale, f'liema punt

1168
00:54:06,570 --> 00:54:08,720
imbagħad tmur lejn id-destinazzjoni finali tagħha.

1169
00:54:08,720 --> 00:54:11,150
>> Iżda billi encrypting dan, inti
jevitaw kwalunkwe minn dawn it-tipi

1170
00:54:11,150 --> 00:54:15,380
ta 'filtri jew l-impożizzjoni li
xi netwerk lokali imponiet.

1171
00:54:15,380 --> 00:54:17,980
U plus, inti għandek
difiża ħafna aktar robusta

1172
00:54:17,980 --> 00:54:19,730
kontra l-persuni Creepy
madwarek li tista

1173
00:54:19,730 --> 00:54:21,300
jkun jippruvaw jisimgħu fuq it-traffiku tiegħek.

1174
00:54:21,300 --> 00:54:24,591
Xorta jista 'jkun hemm nies Creepy hawn
home lura fil-Yale jaraw traffiku tiegħek

1175
00:54:24,591 --> 00:54:28,440
kif toħroġ mill-VPN, iżda mill-inqas
inti stajt imbuttat-theddida farther bogħod.

1176
00:54:28,440 --> 00:54:30,490
U huwa hawnhekk ukoll, kummerċ off.

1177
00:54:30,490 --> 00:54:33,645
>> Issa naturalment, jekk inti fil
Ċina jew anke fil-kafetterija,

1178
00:54:33,645 --> 00:54:35,770
u int tunnel kollha
traffiku tiegħek permezz Yale,

1179
00:54:35,770 --> 00:54:37,590
liema prezz aħna jħallsu forsi?

1180
00:54:37,590 --> 00:54:38,272
>> UDJENZA: Veloċità.

1181
00:54:38,272 --> 00:54:39,480
DAVID J. Malan: Veloċità, id-dritt?

1182
00:54:39,480 --> 00:54:41,430
Hemm ltqajna biex tkun xi matematika
jew xi fanciness involuti

1183
00:54:41,430 --> 00:54:42,574
fil-encryption attwali.

1184
00:54:42,574 --> 00:54:44,990
Jista 'jkun hemm eluf ta'
mili ta 'distanza jew eluf

1185
00:54:44,990 --> 00:54:47,250
ta 'mili ta' kejbils bejn inti u Yale.

1186
00:54:47,250 --> 00:54:49,800
U huwa tassew ħżiena jekk int
fiċ-Ċina, per eżempju,

1187
00:54:49,800 --> 00:54:51,650
u inti tixtieq li jżuru
websajt fiċ-Ċina.

1188
00:54:51,650 --> 00:54:54,230
U għalhekk data tiegħek ser
l-Istati Uniti, u mbagħad lura lejn iċ-Ċina

1189
00:54:54,230 --> 00:54:56,620
sempliċiment għaliex inti qed encrypting
dan permezz ta 'dan mina.

1190
00:54:56,620 --> 00:54:59,960
>> Iżda jsolvi tekniku
u x-xogħol problemi simili.

1191
00:54:59,960 --> 00:55:02,050
Iżda dan kollu jeħodna għall
dawn l-ideat sempliċi ħafna.

1192
00:55:02,050 --> 00:55:06,530
U Harvard, għal dawk kurjuż, għandha
wieħed hawnhekk ukoll, fil vpn.harvard.edu,

1193
00:55:06,530 --> 00:55:09,150
li topera bħad tal Yale.

1194
00:55:09,150 --> 00:55:12,580
>> Allura b'dak kollu li qal, għaliex
huwa dan in-netwerk kollu utli?

1195
00:55:12,580 --> 00:55:14,080
U x'nistgħu tibda tagħmel magħha?

1196
00:55:14,080 --> 00:55:15,630
Well, ejja jagħmlu dan issa aktar reali.

1197
00:55:15,630 --> 00:55:17,610
Dan huwa l-akronimu
li magħhom ħafna minna

1198
00:55:17,610 --> 00:55:22,140
huma probabbilment super familiar-- HTTP--
li stands għat-trasferiment test iper

1199
00:55:22,140 --> 00:55:22,950
protokoll.

1200
00:55:22,950 --> 00:55:26,460
U dan ifisser biss dan huwa
il-lingwa, il-protokoll

1201
00:55:26,460 --> 00:55:29,140
li web browsers u web server jitkellmu.

1202
00:55:29,140 --> 00:55:31,437
>> Il P fil HTTP huwa tabilħaqq protokoll.

1203
00:55:31,437 --> 00:55:33,270
U protokoll huwa biss
sett ta 'konvenzjonijiet.

1204
00:55:33,270 --> 00:55:36,690
Rajna IP-- protocol-- internet
Kontroll ta 'trasmissjoni TCP--

1205
00:55:36,690 --> 00:55:38,290
protocol-- u HTTP.

1206
00:55:38,290 --> 00:55:40,570
Imma dak li huwa dan stupid
ħaġa ta 'protokoll?

1207
00:55:40,570 --> 00:55:41,930
Huwa biss sett ta 'konvenzjonijiet.

1208
00:55:41,930 --> 00:55:43,760
>> Mela jekk jien tip ta 'tinżel
hawn, u nixtieq li greet you.

1209
00:55:43,760 --> 00:55:44,930
Jien ngħid hi, jien jisimni David.

1210
00:55:44,930 --> 00:55:45,600
>> UDJENZA: Luis.

1211
00:55:45,600 --> 00:55:46,475
>> DAVID J. Malan: Luis.

1212
00:55:46,475 --> 00:55:49,360
Għandna din uman stupid
konvenzjoni ta tħawwad idejn hawn.

1213
00:55:49,360 --> 00:55:50,570
Iżda li l-protokoll, id-dritt?

1214
00:55:50,570 --> 00:55:51,470
I estiż naħa tiegħi.

1215
00:55:51,470 --> 00:55:52,530
Luis estiż naħa tiegħu.

1216
00:55:52,530 --> 00:55:53,070
Għamilna dan.

1217
00:55:53,070 --> 00:55:54,790
U mbagħad kompluta, isir.

1218
00:55:54,790 --> 00:55:58,100
>> U dan huwa eżattament l-istess
ispirtu ta 'protokoll kompjuter

1219
00:55:58,100 --> 00:56:02,770
fejn kif fil HTTP, dak li jiġri huwa dan.

1220
00:56:02,770 --> 00:56:05,520
Jekk inti l-kompjuter fuq il-
xellug hawn, u hemm xi web

1221
00:56:05,520 --> 00:56:07,230
server hemm fuq il-lemin.

1222
00:56:07,230 --> 00:56:11,130
U l-kompjuter fuq ix-xellug trid
indikazzjonijiet minn din server.

1223
00:56:11,130 --> 00:56:13,140
Huwa tip ta 'operazzjoni bi-direzzjonali.

1224
00:56:13,140 --> 00:56:15,800
Il-browser fuq ix-xellug
jitlob għal xi web page.

1225
00:56:15,800 --> 00:56:18,404
Il-server fuq il-lemin
jirrispondi ma 'xi web page.

1226
00:56:18,404 --> 00:56:20,570
U aħna ser tara liema forma
dawk tieħu fi ftit mument.

1227
00:56:20,570 --> 00:56:24,311
>> U jirriżulta li dawk computers--
li browser u server, jew klijent

1228
00:56:24,311 --> 00:56:25,310
u server, biex ngħidu hekk.

1229
00:56:25,310 --> 00:56:28,120
Ħafna bħal ristoranti fejn il-
klijent qed titlob xi ħaġa,

1230
00:56:28,120 --> 00:56:31,670
u s-server qed iġġib
lilu jew lilha something-- tikseb

1231
00:56:31,670 --> 00:56:33,170
huwa tip tal-kelma operattiva.

1232
00:56:33,170 --> 00:56:38,560
Litteralment ġewwa tal-pakkett li
browser tiegħi jibgħat minn hawn għal web

1233
00:56:38,560 --> 00:56:40,880
server huwa l-get kelma.

1234
00:56:40,880 --> 00:56:42,700
Like I rridu nġibu aħbarijiet tal-lum.

1235
00:56:42,700 --> 00:56:45,370
I rridu nġibu tiegħi
Għalf aħbarijiet Facebook, jew I

1236
00:56:45,370 --> 00:56:47,330
rridu nġibu xi paġna mis-server.

1237
00:56:47,330 --> 00:56:50,760
>> Speċifikament, dan huwa x'hemm
jiġri ġewwa tal dak il-pakkett.

1238
00:56:50,760 --> 00:56:53,810
So I, bil Cole, essenzjalment
mibgħuta Cole rispons.

1239
00:56:53,810 --> 00:56:56,750
Jekk inti jimmaġina li Cole fil-fatt
riedu stampa ta 'Rick Astley,

1240
00:56:56,750 --> 00:57:00,700
hu seta 'bagħat lili talba
simili fl-ispirtu għal dan.

1241
00:57:00,700 --> 00:57:04,670
Ġewwa tal-pakkett tiegħu lili, fejn
Jien issa ikollhom ir-rwol ta 'Google,

1242
00:57:04,670 --> 00:57:08,270
tkun talba li litteralment
jgħid, jiksbu, u mbagħad slash-- quddiem

1243
00:57:08,270 --> 00:57:10,636
u inti ħadthom probabbilment jidhru
quddiem slashes fil URLs qabel.

1244
00:57:10,636 --> 00:57:13,260
Dan ifisser biss jagħtu me l-inadempjenza
paġna, l-inadempjenza Rick Astley

1245
00:57:13,260 --> 00:57:14,560
stampa f'dan il-każ.

1246
00:57:14,560 --> 00:57:20,100
>> U mill-mod, Cole jitkellem il-lingwa
Verżjoni HTTP 1.1, jew il-protokoll 1.1.

1247
00:57:20,100 --> 00:57:22,090
U jirriżulta hemm
verżjoni anzjani 1.0.

1248
00:57:22,090 --> 00:57:23,910
Iżda kompjuters għandhom tendenza li jużaw 1.1.

1249
00:57:23,910 --> 00:57:27,840
>> It-tieni linja hija ħaġa utli li
se terga 'lura għal forsi qabel twil.

1250
00:57:27,840 --> 00:57:31,900
Iżda huwa biss speċifikazzjoni lili,
ir-riċevitur, li l-ħaġa nixtieq

1251
00:57:31,900 --> 00:57:33,586
huwa www.google.com.

1252
00:57:33,586 --> 00:57:36,340
Għaliex dan huwa ferm possibbli
dawn il-ġranet għall-għexieren,

1253
00:57:36,340 --> 00:57:39,510
mijiet ta 'websajts ma'
ismijiet ta 'dominju differenti għal kulħadd

1254
00:57:39,510 --> 00:57:40,735
jgħixu fuq l-istess server.

1255
00:57:40,735 --> 00:57:42,860
Huwa mhux se jkun veru
tant fil-każ Google.

1256
00:57:42,860 --> 00:57:45,261
Iżda fil-kumpanija iżgħar li
każ, jista 'assolutament jkun.

1257
00:57:45,261 --> 00:57:47,260
Allura Cole huwa biss tip ta '
tqegħid fil-pakkett,

1258
00:57:47,260 --> 00:57:50,840
mill-mod, meta dan jilħaq
indirizz IP tiegħek fuq il-port 80,

1259
00:57:50,840 --> 00:57:54,450
biss tkun żgur li int taf
Irrid www.google.com, mhux

1260
00:57:54,450 --> 00:57:56,740
xi websajt każwali ieħor
fuq l-istess server.

1261
00:57:56,740 --> 00:58:00,360
>> What I imbagħad jirrispondu għal Cole ma ',
fl-aħħar tal-ġurnata, hija stampa.

1262
00:58:00,360 --> 00:58:02,920
Iżda atop li stampa
ġewwa tal-pakkett

1263
00:58:02,920 --> 00:58:05,600
huwa attwalment xi test, fejn I say, OK.

1264
00:58:05,600 --> 00:58:07,970
Nitkellem verżjoni HTTP 1.1 wkoll.

1265
00:58:07,970 --> 00:58:09,200
200.

1266
00:58:09,200 --> 00:58:11,730
Li huwa kodiċi status li
ħafna minna għandna probabbilment

1267
00:58:11,730 --> 00:58:14,185
qatt, għaliex dan ikun ifisser OK.

1268
00:58:14,185 --> 00:58:16,810
U dan huwa tajjeb, minħabba li
ifisser I am jirrispondu b'suċċess

1269
00:58:16,810 --> 00:58:18,040
għat-talba Cole.

1270
00:58:18,040 --> 00:58:21,930
>> What numri jkollhom inti probabilment
tidher fuq il-web li mhumiex OK?

1271
00:58:21,930 --> 00:58:22,780
>> UDJENZA: 404.

1272
00:58:22,780 --> 00:58:24,830
>> DAVID J. Malan: 404-- fajl ma nstabx.

1273
00:58:24,830 --> 00:58:27,520
Allura fil-fatt, kwalunkwe ħin li inti stajt tidher
wieħed minn dawk fajl annoying ma

1274
00:58:27,520 --> 00:58:31,010
Żbalji misjuba, minħabba
il-paġna web huwa mejjet,

1275
00:58:31,010 --> 00:58:34,190
jew għaliex inti mistyped
URL, li ifisser biss

1276
00:58:34,190 --> 00:58:37,600
li l-pakkett ftit li tiegħek
kompjuter riċevuti mis-server

1277
00:58:37,600 --> 00:58:42,670
kien fih messaġġ HTTP
1.1, 404-- ma nstabx.

1278
00:58:42,670 --> 00:58:44,930
Dan il-fajl jew talba
inti ssir ma tinstabx.

1279
00:58:44,930 --> 00:58:48,660
>> Barra minn hekk, ġewwa tal-pakkett
tipikament hija din il-linja, it-tip kontenut.

1280
00:58:48,660 --> 00:58:51,080
Xi kultant huwa HTML,
xi ħaġa li aħna ser dalwaqt tara.

1281
00:58:51,080 --> 00:58:52,225
Kultant huwa JPEG.

1282
00:58:52,225 --> 00:58:53,100
Kultant huwa GIF.

1283
00:58:53,100 --> 00:58:56,060
Xi kultant huwa fajl movie, l-
audio file, kull numru ta 'affarijiet.

1284
00:58:56,060 --> 00:59:00,059
Allura ġewwa tal-pakkett huwa biss
ftit ħjiel dwar dak I am jirċievu.

1285
00:59:00,059 --> 00:59:03,100
Hemm kodiċijiet ta 'stat oħra wkoll, xi
li aħna ser tesplora P stabbiliti sitt,

1286
00:59:03,100 --> 00:59:05,890
u tkun taf stumble madwar
fl P sett seba u / jew tmienja.

1287
00:59:05,890 --> 00:59:08,580
Iżda xi hawnhekk, bħal 404 Rajna.

1288
00:59:08,580 --> 00:59:11,700
Projbit, 403, ifisser bħal
l-permessi huma żbaljati,

1289
00:59:11,700 --> 00:59:14,740
bħal int ma tip ta '
konfigurati b'mod korrett.

1290
00:59:14,740 --> 00:59:17,830
301 u 302, aħna rarament tara viżwalment.

1291
00:59:17,830 --> 00:59:19,150
Iżda jfissru direzzjoni ġdida.

1292
00:59:19,150 --> 00:59:21,650
Kwalunkwe ħin li inti stajt marret biex wieħed
URL u inti kont qed magically

1293
00:59:21,650 --> 00:59:24,410
mibgħuta x'imkien ieħor, li l-
minħabba li l-browser bagħtet lura

1294
00:59:24,410 --> 00:59:27,210
pakkett fih
in-numru 301 jew 302,

1295
00:59:27,210 --> 00:59:30,790
u l-URL li trid
browser tiegħek biex tmur minflok.

1296
00:59:30,790 --> 00:59:32,010
>> 500 huwa horrible.

1297
00:59:32,010 --> 00:59:34,842
Int ser ikollok tara li qabel twil, probabbilment
fl P sett sitt jew P sett sebgħa.

1298
00:59:34,842 --> 00:59:37,050
U dan ġeneralment tfisser
hemm xi bug fil-kodiċi tiegħek,

1299
00:59:37,050 --> 00:59:40,000
għaliex tabilħaqq aħna ser tkun bil-miktub
kodiċi li twieġeb għal talbiet web.

1300
00:59:40,000 --> 00:59:42,110
U inti stajt biss ltqajna xi
żball fil-loġika jew sintassi,

1301
00:59:42,110 --> 00:59:43,820
u s-server ma jistgħux jimmaniġġaw dan.

1302
00:59:43,820 --> 00:59:47,460
>> Mela ejja ara kif nistgħu issa tista 'lieva u
jifhmu dawn it-talbiet kif ġej.

1303
00:59:47,460 --> 00:59:50,716
Jekk immur, ejja ngħidu, google.com.

1304
00:59:50,716 --> 00:59:55,240
Let me mur www.google.com.

1305
00:59:55,240 --> 01:00:01,220
U għall-finijiet ta 'dimostrazzjoni tal-, ejja
tara, I bżonn biex tmur Settings hawn.

1306
01:00:01,220 --> 01:00:03,180
Jien se jmorru biex Fittex Settings.

1307
01:00:03,180 --> 01:00:08,236
U Google dejjem aktar annoying
karatteristiċi, iżda l-karatteristiċi utli.

1308
01:00:08,236 --> 01:00:11,110
Allura Google għandha dan ħaġa bħal instant
riżultati fejn inti tibda ittajpjar,

1309
01:00:11,110 --> 01:00:12,889
u awtomatikament
affarijiet jibdew jidhru.

1310
01:00:12,889 --> 01:00:14,680
U li kollox multa
u teknikament utli,

1311
01:00:14,680 --> 01:00:16,420
u aħna ser jifhmu
qabel twil kif taħdem din.

1312
01:00:16,420 --> 01:00:18,429
Iżda għal issa, jien tidwir
off riżultati istantanji,

1313
01:00:18,429 --> 01:00:20,720
għaliex nixtieq browser tiegħi li
tip ta 'xogħol l-iskola antika hekk

1314
01:00:20,720 --> 01:00:22,940
li nista 'nara x'inhu għaddej.

1315
01:00:22,940 --> 01:00:23,840
>> Allura issa jien lura hawn.

1316
01:00:23,840 --> 01:00:25,090
U jien trid tfittex għal qtates.

1317
01:00:25,090 --> 01:00:30,351
U avviż jien jaraw xi suġġerimenti,
xi suġġerimenti beninni ħafna

1318
01:00:30,351 --> 01:00:30,850
Thankfully.

1319
01:00:30,850 --> 01:00:34,730
U issa jekk I hit Ikteb,
ejja ara dak li jiġri.

1320
01:00:34,730 --> 01:00:35,850
>> Allura hemm xi qtates.

1321
01:00:35,850 --> 01:00:37,540
U l-hit quċċata hija fuq il-Wikipedija.

1322
01:00:37,540 --> 01:00:39,820
Imma llum aħna kura dwar
it-teknoloġija up here.

1323
01:00:39,820 --> 01:00:42,479
Allura l-URL li stajt
intbagħtet hija din hawnhekk.

1324
01:00:42,479 --> 01:00:44,520
U hemm xi Jittieħed I
ma verament jifhem.

1325
01:00:44,520 --> 01:00:47,430
>> Hekk jien ser jimxi 'l quddiem, minħabba
I tip ta 'know kif Google xogħlijiet,

1326
01:00:47,430 --> 01:00:50,700
u jien ser jiddistillaw dan
URL fil-forma sempliċi tagħha.

1327
01:00:50,700 --> 01:00:52,510
U issa jien se hit Ikteb ġdid.

1328
01:00:52,510 --> 01:00:53,360
U għadu jaħdem.

1329
01:00:53,360 --> 01:00:55,800
I jkollhom paġna ta 'riżultati kollha dwar qtates.

1330
01:00:55,800 --> 01:00:58,460
>> Iżda avviż-sempliċità ta 'URL tiegħi.

1331
01:00:58,460 --> 01:01:00,820
Jirriżulta dan huwa kif
ħafna tax-xogħlijiet web.

1332
01:01:00,820 --> 01:01:03,500
Il-web huwa biss ħaġa waħda
mazz ta 'kompjuters

1333
01:01:03,500 --> 01:01:05,320
tmexxija software li jieħdu input.

1334
01:01:05,320 --> 01:01:07,480
Mhuwiex tirċievi opinjonijiet stil sekwenza.

1335
01:01:07,480 --> 01:01:09,670
Mhuwiex linja ta 'kmand
argumenti bħal aħna qed jintużaw biex.

1336
01:01:09,670 --> 01:01:13,449
Huma jieħdu input, dawn is-servers tal-web,
permezz ta 'l-URLs spiss.

1337
01:01:13,449 --> 01:01:15,240
U kull darba inti stajt
mfittxija għal xi ħaġa,

1338
01:01:15,240 --> 01:01:17,448
kwalunkwe ħin li inti stajt logged in
Facebook, kwalunkwe ħin li inti stajt

1339
01:01:17,448 --> 01:01:20,090
jsir xejn interattiva ma
web page, dak li qed isir

1340
01:01:20,090 --> 01:01:24,340
hija effettivament sottomissjoni ta 'formola, hekk
li speak-- kaxxi test, kaxxi kontroll,

1341
01:01:24,340 --> 01:01:27,880
ċrieki ftit, u whatnot li jibgħat
informazzjoni mill inti l-server.

1342
01:01:27,880 --> 01:01:31,960
>> U jirriżulta li l-web
server jaf li tħares lejn dak URL

1343
01:01:31,960 --> 01:01:36,040
u parse, bħal ħarsa lejn din karattru
billi karattru tfittex xi ħaġa

1344
01:01:36,040 --> 01:01:38,000
interessanti wara kwistjoni mark.

1345
01:01:38,000 --> 01:01:40,910
Għax wara kwistjoni mark,
jirriżulta, li jkun ser jiġi

1346
01:01:40,910 --> 01:01:42,730
mazz ta 'pari b'valur ewlenin.

1347
01:01:42,730 --> 01:01:44,570
I tfisser ċavetta = valur.

1348
01:01:44,570 --> 01:01:48,130
U allura jekk hemm multiple-- forsi
l ampersand, xi oħrajn ewlenin = valur,

1349
01:01:48,130 --> 01:01:50,200
ampersand, ta 'ċavetta = valur.

1350
01:01:50,200 --> 01:01:54,560
>> Allura konna tip ta tidher din l-idea
qabel fejn xi ħaġa għandha valur.

1351
01:01:54,560 --> 01:01:55,880
Huwa biss format ġdid hawn.

1352
01:01:55,880 --> 01:01:59,040
U jien biss jafu, b'konvenzjoni,
Google tuża q għall-mistoqsija.

1353
01:01:59,040 --> 01:02:02,670
U mbagħad jekk jien trid tfittex għall-klieb, I
jista manwalment tfittxija għall-klieb bħal dik.

1354
01:02:02,670 --> 01:02:06,360
U allura jien apparentement jkollna
xi rizultati li jinvolvu klieb.

1355
01:02:06,360 --> 01:02:07,727
>> Allura li jidher li jkun interessanti.

1356
01:02:07,727 --> 01:02:10,060
U fil-fatt, dak li għaddej
taħt il-barnuża hija din.

1357
01:02:10,060 --> 01:02:11,460
Let me jagħmlu dan.

1358
01:02:11,460 --> 01:02:13,620
Dan huwa a-- ejja ara.

1359
01:02:13,620 --> 01:02:16,320
Let me jmorru lura fuq
hawn għal ftit mument.

1360
01:02:16,320 --> 01:02:19,810
>> Ser naraw li hemm oħra
modi biex jissottomettu informazzjoni.

1361
01:02:19,810 --> 01:02:25,340
Mela jekk jien jillogja Facebook, jew
Gmail, jew kwalunkwe websajt oħra popolari,

1362
01:02:25,340 --> 01:02:30,720
jidher tip ta 'ħażin jekk kwalunkwe I ittajpjat
fil-kaxxa ta 'tfittxija jispiċċa fil URL tiegħi,

1363
01:02:30,720 --> 01:02:32,850
fil address bar browser tiegħi.

1364
01:02:32,850 --> 01:02:33,690
Għaliex?

1365
01:02:33,690 --> 01:02:35,395
Għaliex huwa li kemmxejn inkwetanti?

1366
01:02:35,395 --> 01:02:39,567

1367
01:02:39,567 --> 01:02:40,067
Yeah?

1368
01:02:40,067 --> 01:02:41,380
UDJENZA: Tip password.

1369
01:02:41,380 --> 01:02:41,720
DAVID J. Malan: Yeah.

1370
01:02:41,720 --> 01:02:44,000
Allura dak jekk dak li stajt
ittajpjat fil hija password tiegħi?

1371
01:02:44,000 --> 01:02:47,881
I tip ta 'Ma rridx hekk ovvjament
viżibbli fil address bar browser tiegħi.

1372
01:02:47,881 --> 01:02:50,630
Waħda, minħabba roommate tiegħi annoying
tendenza li jaraw fuq l-ispalla tiegħi,

1373
01:02:50,630 --> 01:02:53,980
u hu jew hi issa taraw, anki jekk
kien balal meta jien ittajpjar fil,

1374
01:02:53,980 --> 01:02:54,810
ċrieki ftit.

1375
01:02:54,810 --> 01:02:56,010
Issa huwa fil address bar tiegħi.

1376
01:02:56,010 --> 01:02:59,270
>> Barra minn hekk, dak veru dwar Jittieħed
inti għandek tendenza li tip fl-address bar.

1377
01:02:59,270 --> 01:03:00,230
>> UDJENZA: [inaudible]

1378
01:03:00,230 --> 01:03:01,505
>> DAVID J. Malan: X'hemm li?

1379
01:03:01,505 --> 01:03:02,630
UDJENZA: Jiġrilha ntbagħtu.

1380
01:03:02,630 --> 01:03:03,510
DAVID J. Malan: Jiġrilha ntbagħtu.

1381
01:03:03,510 --> 01:03:05,102
U wkoll, jiġrilha mfakkar.

1382
01:03:05,102 --> 01:03:07,060
Minħabba li l-ħin li jmiss
inti tip affarijiet up hemm,

1383
01:03:07,060 --> 01:03:10,440
spiss autocompletes u
jiftakar dak li inti stajt ittajpjat qabel.

1384
01:03:10,440 --> 01:03:13,850
U hekk hemm din l-istorja vera
li parentela tiegħek, jew roommate tiegħek,

1385
01:03:13,850 --> 01:03:16,830
jew min jista 'jimxi permezz ta' l
pretty ħafna tara kull website

1386
01:03:16,830 --> 01:03:19,760
inti żar għaliex dan huwa
illoggjat li address bar.

1387
01:03:19,760 --> 01:03:22,790
>> Barra minn hekk, ejja ngħidu li inti tixtieq li
upload ritratt biex Facebook.

1388
01:03:22,790 --> 01:03:26,520
Kif fid-dinja huma inti
se timplimenta ritratt fil-URL?

1389
01:03:26,520 --> 01:03:30,217
>> Ukoll jirriżulta inti tista 'tagħmel dan f'xi
mod, iżda huwa ċertament mhux ovju.

1390
01:03:30,217 --> 01:03:33,050
U hekk hemm dan mod ieħor ta '
jibgħat informazzjoni fl-istess pakkett,

1391
01:03:33,050 --> 01:03:35,680
mhux permezz ta 'IKOLLOK, iżda permezz
xi ħaġa imsejħa POST.

1392
01:03:35,680 --> 01:03:38,060
U fit-teorija, jidher
pjuttost l-istess.

1393
01:03:38,060 --> 01:03:41,270
Minflok il-kelma IKOLLOK, ngħidu POST,
u allura l-istess tip ta 'format.

1394
01:03:41,270 --> 01:03:43,310
>> Per eżempju, dan huwa
screenshot ta 'dak

1395
01:03:43,310 --> 01:03:46,920
dan jista 'dehra jekk nipprova qtugħ
fis Facebook, li jibgħat me għall-fajl

1396
01:03:46,920 --> 01:03:51,230
imsejħa login.php, li huwa attwalment
għadu sal-ġurnata msemmi bħala tali.

1397
01:03:51,230 --> 01:03:53,910
Huwa l-istess Mark filename
taw lilu ħafna snin ilu.

1398
01:03:53,910 --> 01:03:58,520
Huwa l-programm huwa kiteb fil-PHP permezz
li l-utenti jistgħu login għall-websajt.

1399
01:03:58,520 --> 01:04:00,370
>> Imma għandek bżonn biex tibgħat
xi kontribut addizzjonali.

1400
01:04:00,370 --> 01:04:05,170
U pjuttost milli jmorru wara l-
fajl isem kif għamel qabel ma cats--

1401
01:04:05,170 --> 01:04:09,720
q = cats-- ikun jista 'jimxi aktar baxx fit-talba,
ġewwa fil-fond tal-pakkett jekk inti

1402
01:04:09,720 --> 01:04:12,440
se fejn l-ebda wieħed jista 'jara dan,
u fejn ma jispiċċawx

1403
01:04:12,440 --> 01:04:15,670
fil-browser bar-utent, u għalhekk
ma tiftakarx għall-persuni li Snoop

1404
01:04:15,670 --> 01:04:16,290
madwar.

1405
01:04:16,290 --> 01:04:21,260
>> U hekk hawn indirizz email tiegħi u
password foloz tiegħi fil-fatt imorru.

1406
01:04:21,260 --> 01:04:27,400
U jekk Facebook qiegħed juża
mhux HTTP, HTTPS iżda,

1407
01:04:27,400 --> 01:04:30,710
dan se jkun kriptat kollha,
scrambled, ala Caesar jew Vigenere,

1408
01:04:30,710 --> 01:04:34,960
iżda aktar fancily sabiex ħadd
jista 'attwalment tara din it-talba.

1409
01:04:34,960 --> 01:04:38,120
>> U għalhekk fil-fatt, kwalunkwe ħin għandek
URL li jibda bil HTTPS,

1410
01:04:38,120 --> 01:04:39,560
dan ifisser biss huwa encrypted.

1411
01:04:39,560 --> 01:04:42,710
Iżda fl-aħħar tal-ġurnata, x'hemm
fil-fatt ġewwa ta 'dawn pakketti?

1412
01:04:42,710 --> 01:04:44,070
Dan kien livell super baxx.

1413
01:04:44,070 --> 01:04:46,240
U fortunatament, aħna mhux qed
se neċessarjament ikollhom

1414
01:04:46,240 --> 01:04:49,310
li jmorru livell tant baxx kull darba li
tibda tikteb software interessanti.

1415
01:04:49,310 --> 01:04:51,060
Nistgħu tibda tieħu
l-ideat ta 'ġimgħa

1416
01:04:51,060 --> 01:04:54,020
permezz ħames, wieħed jassumi li hemm
issa huwa din l-infrastruttura li

1417
01:04:54,020 --> 01:04:57,160
tikri us jiktbu software
li topera fuq il-web,

1418
01:04:57,160 --> 01:05:00,120
u li għaddej biex inessu
din il-ġimgħa li ġejjin biex tibda

1419
01:05:00,120 --> 01:05:01,840
tħares lejn xi ħaġa imsejħa HTML.

1420
01:05:01,840 --> 01:05:04,750
Dan huwa l-għalf li huwa saħansitra
aktar profonda ġewwa tal-pakkett,

1421
01:05:04,750 --> 01:05:06,150
imma hija l-għalf aħna qed
ser tibda bil-miktub.

1422
01:05:06,150 --> 01:05:08,020
U huwa l-għalf aktar
interessanti, aħna qed

1423
01:05:08,020 --> 01:05:11,420
ser jikteb programmi li
jibda jiġġenera awtomatikament

1424
01:05:11,420 --> 01:05:15,410
sabiex websajts tagħna mhumiex iebes kodifikati,
imma jieħdu input u jipproduċi output.

1425
01:05:15,410 --> 01:05:18,810
>> Din hi forsi l-web sempliċi
paġna inti tista 'tagħmel fid-dinja.

1426
01:05:18,810 --> 01:05:23,000
I tista 'tabilħaqq jiftħu
xi ħaġa stupid bħal TextEdit

1427
01:05:23,000 --> 01:05:26,160
fuq Mac tiegħi, li biss tagħti me
tieqa test sempliċi bħal dan.

1428
01:05:26,160 --> 01:05:29,510
Utenti PC jkollhom Notepad.ext,
li hija simili ħafna fl-ispirtu.

1429
01:05:29,510 --> 01:05:33,212
>> UI jistgħu litteralment tip
l this-- DOCTYPE HTML,

1430
01:05:33,212 --> 01:05:34,420
li jistenna ftit cryptic.

1431
01:05:34,420 --> 01:05:35,850
Iżda aħna ser terga 'lura għal dan.

1432
01:05:35,850 --> 01:05:38,730
HTML, ma 'dawn stramb
parentesi angolata u slashes,

1433
01:05:38,730 --> 01:05:42,240
ġewwa minnhom issa jien se ngħid
hawnhekk jidħol l-kap tal-paġna web tiegħi.

1434
01:05:42,240 --> 01:05:45,220
Ġewwa dan, I biss
jafu, u tkun taf dalwaqt tkun taf,

1435
01:05:45,220 --> 01:05:47,850
li I tista 'tpoġġi t-titolu tal-paġna tal-web tiegħi.

1436
01:05:47,850 --> 01:05:49,720
U mbagħad taħt il-
kap tal-paġna web huwa

1437
01:05:49,720 --> 01:05:51,972
se jmorru għall-hekk imsejħa
korp tal-paġna web.

1438
01:05:51,972 --> 01:05:54,180
U jien biss indenting biss
bħal fil C sa tip ta 'jżomm

1439
01:05:54,180 --> 01:05:57,620
affarijiet nicely tinqara stylistically.

1440
01:05:57,620 --> 01:06:04,745
U issa jien ser tiffranka dan bħala
fajl fuq id-desktop, imsejħa hello.html tiegħi.

1441
01:06:04,745 --> 01:06:06,770
>> U jien ser jgħidlek dan iva, l-użu HTML.

1442
01:06:06,770 --> 01:06:09,690
Tbiddilx li txt, anke
għalkemm dan kollu huwa fajl test,

1443
01:06:09,690 --> 01:06:12,130
bħad programm C
miktub bil-editur test.

1444
01:06:12,130 --> 01:06:15,080
Għalkemm mhux fil CS50 IDE fil-
mument, biss hawn fuq Mac tiegħi.

1445
01:06:15,080 --> 01:06:18,490
>> U jekk jien issa mur desktop tiegħi,
tkun taf tara hello.html.

1446
01:06:18,490 --> 01:06:20,720
Jekk I ikklikkja darbtejn dan,
din se tiftaħ Chrome.

1447
01:06:20,720 --> 01:06:23,260
U anki jekk dan il-fajl
jiġri li jgħixu fuq id-desktop tiegħi,

1448
01:06:23,260 --> 01:06:26,550
li hija forsi l-aktar sempliċi
web page I tista 'tagħmel.

1449
01:06:26,550 --> 01:06:30,080
>> Avviż li t-titolu tal-
tab mod top up huwa bonjour dinja.

1450
01:06:30,080 --> 01:06:32,470
Il-korp tal-paġna web
huwa tabilħaqq bonjour dinja.

1451
01:06:32,470 --> 01:06:35,830
U kollha jien ghamilt biex tikseb
dan il-punt hija implimentata,

1452
01:06:35,830 --> 01:06:38,342
jew hu li tikteb lingwa ġdida, imsejħa HTML.

1453
01:06:38,342 --> 01:06:40,300
Mhuwiex programmar
lingwa bħal C. Hemm

1454
01:06:40,300 --> 01:06:42,508
mhux se tkun kundizzjonijiet,
u loops, u l-funzjonijiet.

1455
01:06:42,508 --> 01:06:46,560
Huwa lingwa markup, f'liema
każ inti biss tell il tirċievi

1456
01:06:46,560 --> 01:06:48,410
programm dak li inti trid tagħmel.

1457
01:06:48,410 --> 01:06:51,195
Dan ifisser ħej browser,
hawnhekk jidħol paġna HTML.

1458
01:06:51,195 --> 01:06:53,040
Ħej browser, hawnhekk jidħol
il-kap tal-paġna tiegħi.

1459
01:06:53,040 --> 01:06:55,130
Ħej browser, hawnhekk jidħol
il-korp tal-paġna tiegħi.

1460
01:06:55,130 --> 01:06:57,100
Ħej browser, li lilha għall-ġisem.

1461
01:06:57,100 --> 01:06:59,350
Li lilha għall-paġna HTML.

1462
01:06:59,350 --> 01:07:03,560
>> U ma dawk id-definizzjonijiet sempliċi
waħdu, aħna ser dalwaqt tara li wieħed,

1463
01:07:03,560 --> 01:07:05,122
nistgħu jirrappreżentaw dan bħala siġra.

1464
01:07:05,122 --> 01:07:06,080
Iżda aktar fuq dan aktar tard.

1465
01:07:06,080 --> 01:07:08,788
Allura dan se kollu interkonnessjoni li
istrutturi tagħna dejta aktar riċenti.

1466
01:07:08,788 --> 01:07:12,460
Tnejn, aħna ser jintroduċu dan Joke stupid.

1467
01:07:12,460 --> 01:07:15,680
Dan huwa tatwaġġ attwali li
dan Guy kellu fuq għonq tiegħu.

1468
01:07:15,680 --> 01:07:19,660
Huwa probabbilment umoristiċi-ewwel ġimgħa jew
tnejn, u wara dan, forsi mhux tant.

1469
01:07:19,660 --> 01:07:22,960
>> Iżda HTML, u anki l-web
paġna I biss magħmula, mind super

1470
01:07:22,960 --> 01:07:25,670
numbingly disappointing--
biss qal bonjour dinja

1471
01:07:25,670 --> 01:07:27,210
fit-test iswed fuq sfond abjad.

1472
01:07:27,210 --> 01:07:28,680
Żgur nistgħu nagħmlu ħafna aktar.

1473
01:07:28,680 --> 01:07:31,552
U aħna ser nagħmlu dan billi tintroduċi
lingwa oħra msejħa CSS.

1474
01:07:31,552 --> 01:07:34,760
Dan ukoll mhuwiex language-- programmar
ebda loops, u kondizzjonijiet, jew għal linji,

1475
01:07:34,760 --> 01:07:38,470
imma verament, biss livell sintattiku li permezz tiegħu
nistgħu ngħidu, jagħmlu dan it-test big.

1476
01:07:38,470 --> 01:07:39,415
Jagħmlu dan it-test żgħir.

1477
01:07:39,415 --> 01:07:40,040
Dritt allinjata.

1478
01:07:40,040 --> 01:07:40,650
Xellug allinjata.

1479
01:07:40,650 --> 01:07:41,195
Jagħmluha roża.

1480
01:07:41,195 --> 01:07:41,820
Jagħmluha vjola.

1481
01:07:41,820 --> 01:07:42,650
Jagħmluha blu.

1482
01:07:42,650 --> 01:07:44,860
Jew kwalunkwe numru ta '
effetti viżwali oħra.

1483
01:07:44,860 --> 01:07:48,590
U hekk aħna ser tara kif tibda stylizing
paġni web sabiex huma jfittxu b'mod

1484
01:07:48,590 --> 01:07:50,480
eqreb lejn dak li rridu.

1485
01:07:50,480 --> 01:07:56,930
>> U fl-aħħar, għandna tassew ruined
forsi ħafna tat-TV u film għalik.

1486
01:07:56,930 --> 01:07:58,930
Ħsibt aħna'd jispiċċaw hawn
mal sekondi finali tagħna

1487
01:07:58,930 --> 01:08:03,700
fuq clip finali li turi li inti
kif hacking fuq ix-xogħlijiet internet.

1488
01:08:03,700 --> 01:08:06,250
Jekk nistgħu dim l
dwal finali darba.

1489
01:08:06,250 --> 01:08:07,250
>> [Daqq video]

1490
01:08:07,250 --> 01:08:09,520
>> Mod -Nru.

1491
01:08:09,520 --> 01:08:10,650
Jien jkollna Hacked.

1492
01:08:10,650 --> 01:08:11,770
>> -Okorsky?

1493
01:08:11,770 --> 01:08:14,230
>> -No-- Le, dan huwa kbir.

1494
01:08:14,230 --> 01:08:17,074
Huma ħadthom diġà maħruq permezz
l firewall pubbliku NCIS.

1495
01:08:17,074 --> 01:08:19,990
Well, jiżolaw il-node u dump
minnhom fuq in-naħa l-oħra tal-router.

1496
01:08:19,990 --> 01:08:20,990
-Qed nipprova.

1497
01:08:20,990 --> 01:08:23,990
Huwa jiċċaqalqu malajr wisq.

1498
01:08:23,990 --> 01:08:25,179
>> -OH, Dan mhuwiex tajjeb.

1499
01:08:25,179 --> 01:08:27,470
Huma qed jużaw konnessjoni tagħna
[Inaudible] din id-database.

1500
01:08:27,470 --> 01:08:28,458
Qtugħ dan.

1501
01:08:28,458 --> 01:08:28,958
-I Ma jistgħux.

1502
01:08:28,958 --> 01:08:29,454
Huwa attakk punt.

1503
01:08:29,454 --> 01:08:31,438
Hu jew hi biss
għaddejjin wara magna tiegħi.

1504
01:08:31,438 --> 01:08:32,430
>> -Hija Mhux possibbli.

1505
01:08:32,430 --> 01:08:33,847
Hemm DOD encryption minjiera livell.

1506
01:08:33,847 --> 01:08:35,055
Huwa se jieħu xhur biex get--

1507
01:08:35,055 --> 01:08:35,857
-Hey, Dak li huwa dan?

1508
01:08:35,857 --> 01:08:36,398
A video game?

1509
01:08:36,398 --> 01:08:37,886
>> -Nru Tony, aħna qed jkollna Hacked.

1510
01:08:37,886 --> 01:08:40,795
>> -Jekk Huma jiksbu fil-kompjuter Abby, il
in-netwerk NCIS kollu huwa li jmiss.

1511
01:08:40,795 --> 01:08:42,050
>> -I Ma tistax twaqqaf lilu.

1512
01:08:42,050 --> 01:08:43,050
Tagħmel xi ħaġa McGee.

1513
01:08:43,050 --> 01:08:44,550
>> -I've Qatt ma rajt kodiċi bħal dan.

1514
01:08:44,550 --> 01:08:47,432

1515
01:08:47,432 --> 01:08:48,571
-OH.

1516
01:08:48,571 --> 01:08:49,196
-fejn S tmur?

1517
01:08:49,196 --> 01:08:50,604
Abby?

1518
01:08:50,604 --> 01:08:51,520
-I Ma tagħmel xejn.

1519
01:08:51,520 --> 01:08:53,020
Ħsibt li inti għamilt.

1520
01:08:53,020 --> 01:08:54,520
>> -Nru.

1521
01:08:54,520 --> 01:08:57,232
>> -I Għamlet.

1522
01:08:57,232 --> 01:08:58,307
>> [END Daqq]

1523
01:08:58,307 --> 01:09:00,390
DAVID J. Malan: L-aħjar
parti hija żewġ persuni tajping

1524
01:09:00,390 --> 01:09:02,170
fuq it-tastiera fl-istess ħin.

1525
01:09:02,170 --> 01:09:03,200
>> Allura dak lilha għall CS50.

1526
01:09:03,200 --> 01:09:04,700
Aħna ser stick madwar għal ħinijiet tal-uffiċċju.

1527
01:09:04,700 --> 01:09:06,344
U aħna ser tara inti ħin li jmiss.

1528
01:09:06,344 --> 01:09:07,760
[Daqq tal-mużika - "TEMA Seinfeld"]

1529
01:09:07,760 --> 01:09:11,139

1530
01:09:11,139 --> 01:09:11,680
Dan huwa CS50.

1531
01:09:11,680 --> 01:09:17,960

1532
01:09:17,960 --> 01:09:20,854
Ma rridx li tkun pirata.

1533
01:09:20,854 --> 01:09:21,770
SPEAKER 2: Yarr David.

1534
01:09:21,770 --> 01:09:23,700
Huwa Doublet multa inti tkun liebes.

1535
01:09:23,700 --> 01:09:26,450
Lott ta 'Luff f'dak puff.

1536
01:09:26,450 --> 01:09:29,327