Phau Ntawv Xov Xwm hauv Internet
Hauv Internet thiab ntau tus lag luam loj tshaj plaws hauv Internet (IP) sib koom tes rau kev vam khom rau lub Npe Ntawm Qhov Chaw (DNS) los pab tswj tsheb ncaj. Cov DNS tswj lub database ntawm cov npe ntawm cov npe thiab chaw nyob, thiab nws muab kev rau cov computers mus rau cov lus nug cov lus nug. Qee cov neeg hu DNS rau "xov tooj hauv Internet."
DNS thiab World Wide Web
Txhua tus pej xeem cov Web site khiav tawm ntawm cov neeg txuas nrog Internet nrog cov chaw tus IP . Cov Web servers ntawm At.com, piv txwv li, muaj cov chaw nyob xws li 207.241.148.80. Txawm hais tias tib neeg tuaj yeem sau qhov chaw nyob xws li http://207.241.148.80/ rau hauv lawv lub Web browser mus xyuas cov chaw, siv tau cov npe zoo li http://www.about.com/ ntau dua.
Hauv Internet siv DNS ua thoob ntiaj teb lub npe daws teeb meem rau pej xeem cov Web site. Thaum twg ib tug neeg muaj lub npe lub npe mus rau hauv lawv tus browser, DNS saib txog qhov chaw tus IP coj mus rau qhov chaw ntawd, cov ntaub ntawv yuav tsum ua qhov sib txuas sib txuas ntawm qhov Web site browsers thiab Web servers .
DNS Servers thiab lub npe Hierarchy
DNS siv ib tus neeg siv kev sib raug zoo / neeg siv khoom tsim. DNS servers yog cov computers tso npe khaws cia DNS database cov ntaub ntawv (npe thiab chaw nyob), thaum cov neeg siv ntawm lub DNS xws li cov PCs, cov xov tooj thiab lwm cov khoom siv ntawm cov neeg siv tas. DNS servers kuj sib txuas nrog txhua lwm yam, ua cov neeg tau txais kev pab thaum tsim nyog.
Cov DNS tso nws cov servers rau hauv lub hierarchy. Rau hauv Internet, thiaj li hu lub hauv paus lub npe servers nyob rau saum toj ntawm DNS hierarchy. Internet cag lub npe servers tswj DNS cov ntaub ntawv rau DNS cov ntaub ntawv rau cov Web site -top-domains (TLD) (zoo li ".com" thiab ".uk"), uas yog lub npe thiab tus IP chaw ntawm tus thawj (hu ua authoritative ) DNS servers uas yuav tau teb rau nug txog txhua TLD ib lub zuj zus. Servers ntawm qib qis dua ntawm DNS hierarchy taug qab ob theem sau npe thiab chaw nyob (xws li "about.com"), thiab ntxiv cov qib tswj Web puav (zoo li "compnetworking.about.com").
DNS servers yog nruab thiab tswj xyuas los ntawm cov lag luam ntiav thiab Internet hauv lub ntiaj teb. Rau hauv Internet, 13 lub hauv paus servers servers (tiag redundant pas ntawm cov cav tov thoob ntiaj teb) txhawb cov ntsej muag pua pua hauv Internet saum toj kawg nkaus, while About.com muab cov ntaub ntawv pov thawj DNS cov ntaub ntawv rau hauv nws qhov chaw. Cov koom haum tuaj yeem muab DNS rau lawv tus kheej tes hauj lwm nyias, ntawm cov me me.
Ntau - Dab Tsi Yog Tus Neeg Siv Zis DNS?
Configuring tes hauj lwm rau DNS
DNS neeg (hu ua resolvers ) xav siv DNS yuav tsum muaj nws teeb tsa nyob rau hauv lawv lub network. Resolvers cov lus nug cov DNS siv cov chaw nyob ruaj ntseg ( zoo li qub ) ntawm IP ib lossis ntau dua cov DNS servers. Nyob rau hauv lub tsev network, DNS server chaw nyob yuav tsum configured ib zaug ntawm tus router broadband thiab tau tuaj tos los ntawm tus neeg siv khoom , los yog cov chaw nyob ntawm txhua tus neeg tau txais kev kho. Cov neeg ua haujlwm hauv tsev network yuav tuaj yeem siv tau DNS cov chaw nyob ntawm tus neeg siv los ntawm lawv tus neeg muab kev pabcuam hauv Internet los yog cov neeg sab nraud Internet xws li Google Public DNS thiab OpenDNS.
Hom DNS Lookups
DNS feem ntau yog siv los ntawm Web browsers yuav hloov converting Internet sau npe rau cov chaw tus IP . Ntawm ib sab ntawm cov kev txhawb nqa tom qab , lub DNS kuj yog siv rau:
- nrhiav qhov tseeb servers xa xa email
- rov qab lookups uas hloov tus IP chaw nyob rov qab rau tus sau npe
Lub network thov txhawb DNS lookups khiav dhau TCP thiab UDP , chaw nres nkoj 53 los ntawm kev pom zoo.
Saib kuj - Forward and Reverse IP Address Lookup
DNS Caches
Mus zoo dua txheej txheem siab ntawm kev thov, lub DNS siv caching. DNS caches cia cov ntawv luam ntawm cov ntaub ntawv tsis ntev los no-nkag DNS cov ntaub ntawv thaum cov qauv tseem khaws cia rau lawv cov neeg tso cai. Muaj cov ntaub ntawv hauv zos ntawm DNS cov ntaub ntawv cia kom tsim cov network tsheb mus thiab los ntawm cov DNS server hierarchy. Txawm li cas los xij, yog tias ib qho DNS cache ua outdated, teeb meem kev sib txuas ntawm network yuav ua rau. DNS caches kuj tau prone mus tua los ntawm network hackers. Cov neeg khiav dej num hauv network yuav yaug lub DNS cache yog tias tsim nyog siv cov ipconfig thiab cov nqi hluav taws xob zoo ib yam.
Ntxiv - Dab Tsi Yog Ib Qhov Cache?
Dynamic DNS
Txheem DNS kom tag nrho cov IP chaw nyob cov ntaub ntawv khaws tseg rau hauv cov database kom tau tas. Qhov no ua haujlwm fine rau cov kev pabcuam uas raug cov Web site tiam sis tsis yog siv cov cuabyeej uas siv cov IP-xws li "Internet" Web cams lossis home Web servers. Dynamic DNS (DDNS) ntxiv cov txheej txheem network extensions rau DNS kom lub npe daws kev pab rau cov neeg tau txais kev pabcuam.
Ntau qhov chaw thib peb muab dynamic DNS pob tsim rau cov uas xav mus siv lawv lub tsev hauv tsev hauv Internet. Teem kom DDNS ib cheeb tsam hauv Internet yuav tsum tau kos npe nrog cov kws kho mob uas tau xaiv thiab txhim kho software ntxiv rau hauv zos. Tus neeg pabcuam DDNS remotely monitors cuv npe thiab ua rau lub npe DNS hloov npe tshiab.
Ntxiv - Dab tsi yog DNS DNS?
Cawm mus DNS
Microsoft lub Windows Internet Naming Service (WINS) txhawb npe lub npe zoo li DNS tab sis ua haujlwm ntawm qhov rais computers xwb thiab siv qhov chaw sib txawv. WINS yog siv nyob rau qee cov koom tes ntiag tug ntawm lub PCs.
Dot-BIT yog ib qhov qhib qhov project raws li BitCoin technology uas yog ua haujlwm ntxiv rau kev them nyiaj yug rau ib tus ".bit" sau-siab tshaj plaws rau hauv Internet.