Ib tsab xov xwm pab koj kom paub meej tias CDN yog dab tsi.

1. CDN yog dab tsi

Lub npe tag nrho ntawm CDN yog Content Delivery Network, uas yog, cov ntsiab lus faib network. Nws lub hom phiaj yog ntxiv txheej txheej tshiab ntawm CACHE (caching) txheej rau hauv Is Taws Nem uas twb muaj lawm, thiab tshaj tawm cov ntsiab lus ntawm lub vev xaib mus rau ntawm qhov ze tshaj plaws rau tus neeg siv lub network "ntug", kom cov neeg siv tuaj yeem tau txais cov ntsiab lus xav tau nyob ze thiab txhim kho cov neeg siv kev paub. Kev teb ntawm kev nkag mus rau lub vev xaib. Technically daws cov laj thawj xws li me me network bandwidth, coob tus neeg siv tuaj xyuas, kev faib tawm tsis sib xws, thiab lwm yam, thiab txhim kho cov lus teb ceev ntawm cov neeg siv mus saib lub vev xaib.

Txhawm rau muab nws yooj yim, txoj hauv kev ua haujlwm ntawm CDN yog khaws cov peev txheej ntawm koj qhov chaw ntawm CDN nodes nyob thoob plaws ntiaj teb. Thaum cov neeg siv thov cov peev txheej, lawv yuav rov qab cov peev txheej cached ntawm qhov ze tshaj plaws, es tsis txhob xav kom txhua tus neeg siv qhov kev thov rov qab mus rau koj qhov Kev Tau Txais los ntawm qhov chaw tsis txhob muaj kev sib txuas hauv network, txo qhov siab ntawm qhov chaw, thiab ua kom ceev thiab kev paub ntawm cov neeg siv nkag mus rau cov ntaub ntawv.

CDN

Qhov kev ua kom zoo tshaj plaws ntawm CDN ntawm lub network feem ntau yog tshwm sim hauv cov hauv qab no

Kev daws qhov teeb meem "ib mais" ntawm lub server sab

Txo lossis txawm tshem tawm qhov cuam tshuam ntawm kev sib txuas ntawm cov fwj ntawm cov neeg ua haujlwm sib txawv

Yooj yim rau export bandwidth siab ntawm cov xeev

Txo qhov siab ntawm lub nraub qaum network

Optimized kev faib cov ntsiab lus kub hauv Internet

2. Txoj hauv kev ua haujlwm ntawm CDN

CDN 002

Raws li tuaj yeem pom los ntawm daim duab saum toj no, cov txheej txheem rau tus neeg siv nkag mus rau lub vev xaib uas tsis siv CDN caching yog raws li hauv qab no:

Tus neeg siv nkag mus rau lub npe sau npe mus ntsib, thiab lub operating system nug LocalDns rau tus IP chaw nyob ntawm lub npe sau

LocalDns queries ROOT DNS rau tus neeg rau zaub mov tso cai ntawm lub npe sau (qhov no xav tias LocalDns cache tas sijhawm)

ROOT DNS teb rau lub npe sau npe tso cai dns cov ntaub ntawv rau LocalDns

Tom qab LocalDns tau txais kev tso cai dns cov ntaub ntawv ntawm lub npe sau, nws tseem mus nug tus IP chaw nyob ntawm lub npe sau los ntawm kev tso cai dns ntawm lub npe sau.

Tom qab sau npe tso cai dns nug cov npe sau npe, nws teb rau LocalDns

LocalDns yuav tau txais lub npe ip chaw nyob thiab teb rau tus neeg siv khoom

Tom qab tus neeg siv tau txais qhov chaw nyob IP ntawm lub npe sau npe, nws mus xyuas lub vev xaib server

Lub vev xaib server teb rau qhov kev thov thiab xa cov ntsiab lus rov qab rau tus neeg siv khoom

Kev nkag mus rau CDN

CDN 003

Los ntawm daim duab saum toj no, peb tuaj yeem pom tias cov txheej txheem nkag ntawm lub vev xaib tom qab siv CDN cache ua:

Tus neeg siv nkag mus rau lub npe sau npe mus ntsib, thiab lub operating system nug LocalDns rau tus IP chaw nyob ntawm lub npe sau.
LocalDns queries ROOT DNS rau tus neeg rau zaub mov tso cai ntawm lub npe sau (qhov no xav tias LocalDns cache tas sijhawm)
ROOT DNS teb rau lub npe sau npe tso cai dns cov ntaub ntawv rau LocalDns
Tom qab LocalDns tau txais kev tso cai dns cov ntaub ntawv ntawm lub npe sau, nws tseem mus nug tus IP chaw nyob ntawm lub npe sau los ntawm kev tso cai dns ntawm lub npe sau.
Tom qab sau npe tso cai dns nug cov npe sau npe (feem ntau CNAME), nws teb rau LocalDns
Tom qab LocalDns tau txais cov ntaub ntawv sau npe sau npe, nws nug tus IP chaw nyob ntawm lub npe sau los ntawm lub sijhawm ntse DNS
Smart Scheduling DNS Teb rau LocalDns nrog qhov zoo tshaj plaws CDN node ip chaw nyob raws li qee qhov algorithms thiab cov tswv yim (xws li static topology, muaj peev xwm, thiab lwm yam)
LocalDns yuav tau txais lub npe ip chaw nyob thiab teb rau tus neeg siv khoom
Tom qab tus neeg siv tau txais qhov chaw nyob IP ntawm lub npe sau npe, nws mus xyuas lub vev xaib server
CDN node server teb rau qhov kev thov thiab xa cov ntsiab lus rov qab rau tus neeg siv khoom. (Ntawm ib sab, tus neeg rau zaub mov cache khaws nws hauv zos rau kev siv tom qab, thiab ntawm qhov tod tes, rov qab cov ntaub ntawv tau txais mus rau tus neeg siv khoom kom ua tiav cov txheej txheem kev pabcuam cov ntaub ntawv)

Los ntawm kev txheeb xyuas saum toj no, peb tuaj yeem txiav txim siab tias txhawm rau ua tiav kev nkag mus rau cov neeg siv zoo tib yam (tus neeg siv khoom tsis tas yuav ua ib qho kev teeb tsa tom qab siv lub cache), nws yuav tsum siv DNS (Domain Name Resolution) los coj cov neeg siv. nkag mus rau Cache server kom ua tiav cov kev pabcuam pob tshab. Txij li thawj kauj ruam rau cov neeg siv mus xyuas lub vev xaib yog lub npe daws teeb meem, nws yog qhov yooj yim tshaj plaws thiab zoo tshaj plaws los coj cov neeg siv mus ntsib los ntawm kev hloov DNS.

Cheebtsam ntawm CDN network

Rau cov neeg siv Is Taws Nem zoo tib yam, txhua qhov CDN node sib npaug rau lub vev xaib server muab tso rau ib puag ncig nws.

Los ntawm DNS takeover, tus neeg siv qhov kev thov yog pob tshab qhia mus rau ntawm qhov ze tshaj plaws, thiab CDN server nyob rau hauv cov node yuav teb rau tus neeg siv qhov kev thov ib yam li tus thawj server ntawm lub vev xaib. Txij li thaum nws nyob ze rau tus neeg siv, lub sij hawm teb yuav tsum ceev dua.

Lub voj voog ncig los ntawm lub voj voog dotted hauv daim duab saum toj no yog txheej CDN, uas nyob nruab nrab ntawm tus neeg siv khoom thiab lub vev xaib server.

Intelligent teem sijhawm DNS (xws li f5's 3DNS)

Smart Scheduling DNS yog qhov tseem ceeb hauv kev pabcuam CDN. Thaum tus neeg siv mus ntsib lub vev xaib uas koom nrog CDN kev pabcuam, lub npe sau npe daws teeb meem yuav raug daws thaum kawg los ntawm "Smart Scheduling DNS".

Los ntawm cov txheej txheem teev tseg ua ntej, nws muab cov neeg siv nrog qhov chaw nyob ze tshaj plaws rau tus neeg siv lub sijhawm ntawd, kom tus neeg siv tau txais kev pabcuam sai.

Nyob rau tib lub sijhawm, nws yuav tsum tswj hwm kev sib txuas lus nrog CDN nodes faib nyob rau hauv ntau qhov chaw, taug qab cov xwm txheej kev noj qab haus huv, muaj peev xwm thiab lwm yam ntaub ntawv ntawm txhua lub node, thiab xyuas kom meej tias tus neeg siv qhov kev thov raug muab faib rau qhov chaw nyob ze tshaj plaws.

Cache muaj nuj nqi pabcuam

Load ntsuas khoom (xws li lvs, BIG / IP ntawm F5)

Cov ntsiab lus Cache server (xws li squid)

muab faib cia

3. Kev piav qhia cov ntsiab lus

CNAME ntaub ntawv

CNAME yog ib tug alias (Canonical Name); nws tuaj yeem siv los daws cov npe sau npe rau lwm lub npe sau npe. Thaum lub DNS system nug lub npe ntawm sab laug ntawm CNAME, nws yuav tig mus rau lub npe ntawm sab xis ntawm CNAME thiab tom qab ntawd nug, txhua txoj hauv kev mus rau PTR kawg lossis Ib Lub Npe, nws yuav teb tsuas yog tom qab ua tiav. nug, txwv tsis pub nws yuav ua tsis tiav.

Piv txwv li, yog tias koj muaj ntau cov ntaub ntawv khaws cia ntawm lub server, koj siv docs.example.com nkag mus rau cov peev txheej no, tab sis koj cov ntaub ntawv.example.com kuj xav nkag mus rau cov peev txheej no, ces koj tuaj yeem ntxiv CNAME cov ntaub ntawv rau koj qhov kev daws teeb meem DNS. tus muab kev pabcuam, taw tes rau document.example.com, docs.example.comadd Tom qab cov ntaub ntawv CNAME no, tag nrho cov ntaub ntawv nkag mus rau cov ntaub ntawv.example.comrequests yuav raug xa mus rau docs.example.com kom tau txais cov ntsiab lus tib yam.

CNAME lub npe

Thaum nkag mus rau CDN, tom qab ntxiv cov npe nrawm hauv CDN tus neeg muab kev pabcuam, koj yuav tau txais CNAME lub npe sau npe rau koj los ntawm CDN. Koj yuav tsum tau ntxiv CNAME cov ntaub ntawv rau koj qhov chaw muab kev daws teeb meem DNS los taw qhia koj lub npe nrawm rau lub npe CNAME Domain no, kom txhua qhov kev thov rau lub npe sau npe no yuav raug xa mus rau CDN node kom ua tiav cov txiaj ntsig nrawm.

DNS

DNS stands rau Domain Name System, uas txhais tau hais tias sau npe daws qhov kev pabcuam. Nws lub luag haujlwm hauv Is Taws Nem yog hloov lub npe sau rau hauv IP chaw nyob uas tuaj yeem lees paub los ntawm lub network. Tib neeg siv los cim cov npe sau npe, tab sis cov tshuab tsuas paub txog IP chaw nyob. Muaj kev sib txuas lus ib-rau-ib ntawm cov npe sau npe thiab IP chaw nyob. Kev hloov dua siab tshiab ua haujlwm ntawm lawv yog hu ua lub npe daws teeb meem. Domain lub npe daws teeb meem yuav tsum tau ua kom tiav los ntawm ib tug tshwj xeeb sau npe daws teeb meem server. Cov txheej txheem yog tsis siv neeg. Piv txwv li: www.baidu.com nkag mus thaum nthwv dej hauv Is Taws Nem yuav raug hloov mus rau 220.181.112.143.

Cov chaw muab kev daws teeb meem DNS feem ntau suav nrog: Alibaba Cloud Resolution, Wanwang Resolution, DNSPod, Xinwang Resolution, Route53 (AWS), Dyn, Cloudflare, thiab lwm yam.

Rov qab mus rau qhov chaw host

Back-to-origin host: Tus tswv tsev rov qab mus rau keeb kwm txiav txim siab qhov chaw tshwj xeeb ntawm qhov chaw keeb kwm uas qhov kev thov rov qab mus rau keeb kwm nkag.

Piv txwv 1: Lub vev xaib yog lub npe sau npe. Lub vev xaib www.a.comis, thiab tus tswv tsev rov qab mus rau qhov chaw yog www.b.com. Tom qab ntawd qhov kev thov rov qab mus rau qhov chaw tiag tiag yog tus IP daws rau 'www.a.com, thiab lub vev xaib www.b.com ntawm tus tswv tsev sib tham

Piv txwv 2: Lub vev xaib yog IP qhov chaw yog 1.1.1.1, thiab tus tswv tsev rov qab yog www.b.com, tom qab ntawd qhov tseeb rov qab mus rau qhov chaw yog www.b.com ntawm tus tswv tsev sib 1.1.1.1

Cov txheej txheem rov qab mus rau qhov chaw

Cov txheej txheem siv thaum xa rov qab mus rau qhov chaw zoo ib yam nrog cov txheej txheem siv thaum tus neeg siv nkag mus rau cov peev txheej, uas yog, yog tias tus neeg siv HTTPS thov cov peev txheej, yog tias cov peev txheej tsis raug khaws cia ntawm CDN node, cov node yuav siv. tib HTTPS txoj kev rov qab mus rau qhov chaw kom tau txais cov peev txheej; Ib yam li ntawd, yog tus neeg thov siv HTTP raws tu qauv, CDN node kuj siv HTTP raws tu qauv thaum rov qab mus rau qhov chaw.

Pom zoo cov chaw zov me nyuam, kev sib koom tes network, metro-politan network, xauj kab, tsaus fiber ntau network interconnections ntaus ntawv,

DWDM OTN platform, HT6000 thiab HT6800.