255.255.255.0 Subnet Daim Npog Qhov Ncauj

Lub npog qhov ncauj qhov ntswg 255.255.255.0 qhov chaw nyob yog qhov khoos phis tshaj plaws hauv lub khoos phis ntawm cov computers uas txuas nrog Internet Protocol (IPv4) . Dhau li ntawm nws siv nyob hauv tsev network routers , koj yuav tau ntsib no daim npog ntsej muag ntawm kev sib tw hauv network xws li CCNA .

Subnets ua fences virtual, splitting ib ntu ntawm IP chaw nyob rau hauv me me. Qhov kev xyaum no txo ​​kev siv lub lag luam thiab tso cai rau kev nkag mus thoob cov thoob tshooj.

Ib daim npog lub subnet qhia txog tus kheej lub subnet.

255.255.255.0 thiab Subnetting

Traditional subnets tau ua hauj lwm nrog cov kev sib txuas lus hauv chav kawm uas faib qhov chaw tus IP nyob rau hauv ib ntawm tsib cov chav kawm (Chav Kawm A / B / C / D / E) raws li tus nqi ntawm tus IP chaw nyob.

Lub npog qhov ncauj qhov ntswg 255.255.255.0 hloov mus rau qhov nqi 32-ntsis binary:

Cov kab ntawv 0 ntawm daim npog ntsej muag ntawm IP ntau yam ntawm cov khoom xa xov subnet-8 los yog txog 256 chaw nyob rau hauv rooj plaub no. Ib qho xov tooj ntawm cov lag luam me me kuj muaj peev xwm txhais tau los ntawm kev hloov lub npog ncauj raws li qhia hauv qab rooj.

Cov Hauj Lwm Hauv Cov Qub Muab Raws Li 255.255.255 Npog Npaj Tseg
Daim npog qhov ncauj Subnetworks Nodes / Subnet
255.255.255.0 1 254
255.255.255.128 2 126
255.255.255.192 4 62
255.255.255.224 8 30
255.255.255.240 16 14
255.255.255.248 32 6
255.255.255.252 64 2


Ib qho khom nqi xov tooj ntawm sab nrauv (tseem hu ua netmask ) ua rau qee qhov kev sib txuas ntawm network txuas .

Subnets thiab CIDR

Nyob rau hauv cov qauv kev cai classful, ntau qhov chaw tsis siv IP raug khib vim cov neeg muab kev pab cuam hauv internet thiab cov tuam txhab loj muab tshwj tseg cov chaw uas tsis tuaj yeem koom tau.

Ntau cov hauv internet tom qab hloov dua siab tshiab rau cov tsis muaj kev sib txuas ntawm IP los txhawb cov kev cai tuav qis thiab ua kom muaj kev cia siab rau kev thov rau IPv4 chaw nyob hauv xyoo 1990.

Cov chav kawm tsis tau xhauv tus sawv cev ntawm cov kev cai lij choj subnet ua rau cov cim ntawm cov ntawv cim xeeb raws li tus naj npawb ntawm 1 tus lej hauv daim npog ntsej muag.

Classless Inter-Domain Routing shorthand sau ib tus IP chaw nyob thiab nws lub khwb ntawm lub npog ncauj hauv daim ntawv:

xxx.xxx.xxx.xxx/n

Ntawm no, n naj npawb ntawm 1 thiab 31 uas yog tus naj npawb ntawm 1 seem ntawm lub npog ncauj.

CIDR txhawb cov tsis muaj chaw nyob hauv IP thiab koom nrog cov qhov ntsej muag network nrog IP network cov naj npawb ywj pheej ntawm lawv cov chav kawm. Cov kev taw qhia uas txhawb CIDR pom txog cov kev sib txuas ntawm cov tes hauj lwm no, txawm tias lawv tuaj yeem sawv cev ntawm ntau cov kev cai lij choj.

Cov Chav Kawm Network

InterNIC lub koom haum uas tswj cov npe sau npe hauv internet faib cov IP chaw rau hauv cov chav kawm. Cov feem ntau ntawm cov no yog cov chav kawm A, B, thiab C. Cov chav kawm C cov kev siv txhua tus siv lub khoos phis ntawm lub npog ntawm 255.255.255.0.

Siv 255.255.255.0 ua tus IP Chaw Nyob

Txawm hais tias qhia nyob rau hauv daim ntawv ntawm tus IP chaw tus xov tooj, network pab tau tsuas yog siv 255.255.255.0 raws li lub npog ncauj thiab tsis ua IP chaw ua haujlwm. Sim siv tus xov tooj no (los yog ib tus IP naj npawb uas pib nrog 255) raws li qhov chaw nyob ntawm tus ntaus ntawv ua rau qhov kev sib txuas ntawm IP txuas mus tsis tau vim qhov txhais cov zauv nyob ntawm IP networks.