Qhov txawv ntawm QoS thiab CoS

2024 Tus sau: Alex Aldridge | [email protected]. Kawg hloov kho: 2024-01-17 23:34

QoS vs CoS

Hauv computer networks, muaj ntau txoj hauv kev los txhim kho cov ntaub ntawv xa mus zoo. Txoj kev pom tseeb yog nthuav dav bandwidth thiab txhim kho qhov nrawm. Tab sis puas muaj ib txoj hauv kev los txhim kho qhov no los ntawm kev khaws cov khoom siv uas twb muaj lawm hauv pob ntawv hloov pauv? Lub tswv yim no tuaj raws li, kev faib cov ntaub ntawv thav ntawv nyob rau hauv cov nqe lus ntawm "hom ntaub ntawv", ua ntej lawv, thiab hloov mus rau hauv lub network raws li lawv qhov tseem ceeb theem. Qhov no pab cov ntaub ntawv nrog cov qib tseem ceeb dua kom muaj qhov ua ntej tshaj cov ntaub ntawv tseem ceeb tsawg. Cov ntaub ntawv thav ntawv nrog cov qib tseem ceeb dua yuav muaj ntau dua thiab ntau dua los siv kev sib kis nruab nrab, uas txhais tau tias bandwidth siab dua. Qhov no yuav ua rau kev siv tau zoo ntawm bandwidth. CoS (Class of Service) thiab QoS (Kev Pabcuam Zoo) ua lub luag haujlwm tseem ceeb hauv "Kev faib tawm" thiab "Prioritizing" cov ntaub ntawv thav ntawv kom ua tau raws li qhov xav tau saum toj no.

CoS (Class of Service)

Class of Service (CoS) yog ib qho txheej txheem los pab pawg cov ntaub ntawv zoo sib xws ua ke, thiab muab cov ntawv sau nrog "qhov tseem ceeb" rau txhua pab pawg. IEEE 802.1p tus qauv ntawm IEEE 802.1 (kev sib koom tes thiab Kev Tswj Xyuas Network) chav kawm muab txheej 2 hloov pauv los ua kev faib tawm thiab kev ua ntej hauv cov ntaub ntawv thav ntawv. Qhov no ua haujlwm hauv MAC (Media Access Control) txheej hauv OSI qauv. IEEE 802.1p ncej header suav nrog 3-ntsis teb los txhais yim qib tseem ceeb.

PCP

Network priority Acronym yam ntxwv tsheb 1 0 (qis tshaj) BK Background 0 1 BE 2 2 EE Kev Ua Haujlwm Zoo 3 3 CA Critical Applications 4 4 VI Video, < 100 ms latency 5 5 VO Voice, < 10 ms latency 6 6 IC Internetwork Control 7 7 (siab tshaj) NC Network Control

Raws li qhov no, 7^th (siab tshaj plaws) theem ntawm qhov tseem ceeb yog muab rau Network Control thav ntawv, thiab qib kawg (0^th thiab 1^{st) raug xa mus rau keeb kwm yav dhau thiab kev siv zog zoo tshaj plaws.}

QoS (Quality of Service)

QoS yog ib lub tswv yim los tswj cov kev sib txuas hauv network raws li qhov tseem ceeb ntawm cov thav ntawv. Cov theem tseem ceeb yog txhais los ntawm CoS, thiab QoS siv cov txiaj ntsig no los tswj kev tsheb khiav hauv txoj kev sib txuas lus raws li lub koom haum txoj cai. Los ntawm txoj kev no, cov peev txheej network uas twb muaj lawm tuaj yeem siv tau zoo, txhawm rau txhim kho cov ntaub ntawv xa mus. Muaj ob peb lub network yam ntxwv cuam tshuam nrog QoS. Lawv yog Bandwidth (Tus nqi ntawm cov ntaub ntawv hloov chaw), Latency (Qhov siab tshaj plaws cov ntaub ntawv hloov chaw ncua sij hawm ntawm qhov chaw thiab qhov chaw), Jitter (Qhov txawv ntawm latency) thiab Kev Ntseeg (Qhov feem pua ntawm cov pob ntawv pov tseg los ntawm t lub router).

Muaj ntau cov txheej txheem los txhais QoS xws li Int-Serv (Integrated Services), Diff-Serv (Differential Services) thiab MPLS (Multiprotocol Label Switching). Nyob rau hauv Integrated Service qauv, Resource Reservation Protocol (RSVP) yog siv los thov thiab khaws cov peev txheej hauv lub network uas tuaj yeem siv rau cov ntaub ntawv tseem ceeb. Hauv Cov Qauv Sib Txawv Sib Txawv, Diff-Serv cim cov pob ntawv nrog cov lej sib txawv raws li hom kev pabcuam. Routing pab kiag li lawm siv cov qhab nia rau queue cov ntaub ntawv thav ntawv raws li lawv qhov tseem ceeb. MPLS yog dav siv raws tu qauv; Lub hom phiaj tseem ceeb yog muab kev tswj hwm bandwidth thiab kev pabcuam zoo rau IP thiab lwm yam kev cai.

Dab tsi yog qhov txawv ntawm CoS thiab QoS?

• CoS txhais cov theem tseem ceeb thiab QoS tswj kev khiav tsheb raws li cov qib tseem ceeb tau teev tseg.

• CoS tsis lav qhov bandwidth ruaj khov lossis lub sijhawm xa khoom, tab sis QoS lav ruaj bandwidth rau cov ntawv thov tseem ceeb.

• CoS ua haujlwm ntawm txheej 2 hauv OSI tom qab, whereas QoS yog siv hauv txheej 3.

• Cov thawj coj hauv network tuaj yeem teeb tsa QoS hauv lub network tau zoo raws li lub koom haum xav tau, tab sis cov kev hloov pauv hauv CoS, tsis muab cov txiaj ntsig ntau dua li QoS muaj.

• CoS cov txheej txheem yooj yim dua thiab tuaj yeem ntsuas tau yooj yim thaum lub network loj hlob. Piv rau CoS, QoS ua ntau dua thiab nyuaj dua li lub network thiab xav tau cov ntaub ntawv tseem ceeb nce ntxiv.