Backplane bandwidth=tus naj npawb ntawm cov chaw nres nkoj × chaw nres nkoj tus nqi × 2

Tswv yim: Rau Layer 3 hloov, nws yog qhov tsim nyog hloov pauv tsuas yog tias tus nqi xa mus thiab rov qab bandwidth ua tau raws li qhov xav tau yam tsawg kawg nkaus, ob qho tib si yog qhov tseem ceeb.

Piv txwv li,

Yuav ua li cas hloov pauv muaj 24 chaw nres nkoj,

Backplane bandwidth=24 * 1000 * 2/1000=48Gbps.

2 Cov pob ntawv xa tawm tus nqi ntawm cov txheej thib ob thiab thib peb

Cov ntaub ntawv hauv lub network yog tsim los ntawm cov ntaub ntawv pob khoom, thiab kev ua haujlwm ntawm txhua pob ntawv siv cov peev txheej. Kev xa tawm tus nqi (tseem hu ua throughput) yog hais txog tus naj npawb ntawm cov ntaub ntawv packets dhau ib lub sij hawm tsis muaj pob ntawv poob. Kev xa tawm yog zoo li cov tsheb khiav ntawm kev hla hla, thiab nws yog qhov tseem ceeb tshaj plaws ntawm Txheej Txheej 3 hloov, uas cim qhov kev ua tau zoo ntawm kev hloov. Yog tias qhov kev xa tawm me me dhau lawm, nws yuav dhau los ua lub kaw lus hauv lub network thiab muaj kev cuam tshuam tsis zoo rau kev sib kis ntawm tag nrho lub network. Kev hloov pauv yuav tsum muaj peev xwm ua tiav kev hloov pauv ntawm cov xaim ceev, uas yog, qhov hloov pauv mus txog cov ntaub ntawv xa mus ceev ntawm cov kab sib kis, kom tshem tawm cov kev hloov pauv mus rau qhov loj tshaj plaws. Rau txheej txheej 3 core hloov, yog tias nws xav tau kom ua tiav qhov tsis thaiv kev sib txuas hauv network, tus nqi tuaj yeem tsawg dua lossis sib npaug rau tus txheej txheem nominal 2 pob ntawv xa mus thiab tus nqi yuav tsawg dua lossis sib npaug rau lub npe txheej 3 pob ntawv forwarding tus nqi, ces tus hloov yog ua ob thiab peb txheej. Kab nrawm tuaj yeem ua tiav thaum txheej txheej hloov.

Ces tus qauv yog raws li nram no

Throughput (Mpps) {{0}} Tus naj npawb ntawm 10-Gigabit ports × 14.88 Mpps ntxiv rau Tus lej Gigabit ports × 1.488 Mpps ntxiv rau Tus lej ntawm 100-Mbit ports × 0.1488 Mpps.

Yog tias qhov kev suav dhau los tsawg dua qhov kev hloov pauv ntawm koj qhov hloov pauv, nws tuaj yeem ua tiav cov xov hlau ceev.

Ntawm no, yog tias muaj 10-megabit ports thiab 100-megabit ports, lawv yuav raug suav, thiab yog tias lawv tsis yog, lawv tuaj yeem tsis quav ntsej.

Piv txwv li,

Rau kev hloov pauv nrog 24 Gigabit chaw nres nkoj, nws qhov kev teeb tsa tag nrho yuav tsum ncav cuag 24 × 1.488 Mpps=35.71 Mpps kom ntseeg tau tias tsis thaiv cov pob ntawv hloov pauv thaum txhua qhov chaw nres nkoj ua haujlwm ntawm cov xov hlau ceev. Ib yam li ntawd, yog tias qhov hloov pauv tuaj yeem muab txog 176 Gigabit chaw nres nkoj, tom qab ntawd nws qhov kev xa tawm yuav tsum yog tsawg kawg 261.8 Mpps (176 × 1.488 Mpps=261.8 Mpps), uas yog qhov tseeb tsis yog kev thaiv cov qauv tsim.

Yog li, yuav ua li cas kom tau 1.488Mpps?

Tus qauv ntsuas ntawm pob ntawv xa mus kab nrawm yog raws li tus naj npawb ntawm 64byte cov ntaub ntawv pob ntawv (cov pob ntawv tsawg kawg) xa mus rau ib chav tsev raws li qhov ntsuas ntsuas. Rau Gigabit Ethernet, txoj kev suav yog raws li hauv qab no: 1,000,000,000bps/8bit/(64 plus 8 plus 12)byte=1,488,095pps Nco tseg: Thaum Ethernet thav duab yog 64bytes, 8byte ncej header thiab Tsau overhead ntawm 12byte ncej sib txawv. Yog li ntawd, thaum ib kab-ceev Gigabit Ethernet chaw nres nkoj xa mus rau 64byte pob ntawv, cov pob ntawv xa mus yog 1.488Mpps. Qhov chaw nres nkoj xa mus ntawm Fast Ethernet yog raws nraim ib feem kaum ntawm Gigabit Ethernet, uas yog 148.8kpps.

Peb tuaj yeem siv cov ntaub ntawv no.

Yog li ntawd, yog hais tias cov saum toj no peb tej yam kev mob (backplane bandwidth, pob ntawv xa mus rau tus nqi) tuaj yeem ua tau raws li, peb hais tias qhov hloov pauv tseem ceeb no yog qhov tseeb thiab tsis thaiv.

Feem ntau, ib qho kev hloov uas ua tau raws li ob qho kev xav tau yog qhov tsim nyog hloov.

Ib qho kev hloov pauv nrog lub dav hlau rov qab loj thiab qhov kev sib tw me me, ntxiv rau kev tuav lub peev xwm los txhim kho thiab nthuav dav, muaj teeb meem nrog software efficiency / tshwj xeeb nti Circuit Court tsim; lub backplane kuj me me. Ib qho kev hloov pauv nrog qhov loj dhau los muaj qhov ua tau zoo tag nrho. Txawm li cas los xij, cov neeg tsim khoom tshaj tawm tuaj yeem ntseeg tau rau qhov backplane bandwidth, tab sis cov neeg tsim khoom tshaj tawm tsis tuaj yeem tso siab rau qhov kev tshaj tawm, vim tias tom kawg yog tus nqi tsim, thiab qhov kev sim no nyuaj heev thiab tsis tshua muaj qhov tseem ceeb.

3. Scalability

Scalability yuav tsum muaj ob yam:

1. Lub qhov yog siv rau nruab ntau yam kev ua haujlwm modules thiab interface modules. Txij li cov naj npawb ntawm cov chaw nres nkoj muab los ntawm txhua qhov interface module yog qhov tseeb, tus naj npawb ntawm cov slots hauv paus txiav txim siab tus naj npawb ntawm cov chaw nres nkoj uas qhov hloov pauv tuaj yeem haum. Tsis tas li ntawd, tag nrho cov kev ua haujlwm modules (xws li super engine module, IP suab module, ncua kev pab cuam module, network xyuas module, kev ruaj ntseg kev pab module, thiab lwm yam) yuav tsum tau nyob rau hauv ib tug slots, yog li tus naj npawb ntawm slots fundamentally txiav txim siab qhov scalability ntawm tus tes hloov. .

2. Tsis muaj qhov tsis ntseeg tias ntau hom kev txhawb nqa modules (xws li LAN interface modules, WAN interface modules, ATM interface modules, ncua kev ua haujlwm modules, thiab lwm yam), lub zog scalability ntawm qhov hloov. Siv LAN interface module ua piv txwv, nws yuav tsum suav nrog RJ-45 modules, GBIC modules, SFP modules, 10Gbps modules, thiab lwm yam, kom tau raws li qhov xav tau ntawm cov cheeb tsam nyuaj thiab kev siv network hauv cov network loj thiab nruab nrab.

4. Txheej 4 hloov

Txheej 4 hloov pauv yog siv los ua kom nkag tau sai rau cov kev pabcuam network. Hauv Txheej 4 hloov, lub hauv paus rau kev txiav txim siab kis tau tus mob tsis yog tsuas yog MAC chaw nyob (txheej txheem 2 choj) lossis qhov chaw / chaw nyob (txheej 3 routing), tab sis kuj yog TCP / UDP ( Txheej 4) daim ntawv thov chaw nres nkoj, uas yog tsim los rau high-speed intranet daim ntawv thov. Ntxiv nrog rau qhov kev sib npaug ntawm kev ua haujlwm, plaub-txheej hloov pauv kuj tseem txhawb nqa kev sib kis khiav haujlwm raws li hom ntawv thov thiab tus neeg siv ID. Tsis tas li ntawd, Layer 4 hloov zaum ncaj qha rau pem hauv ntej ntawm tus neeg rau zaub mov, nrog rau kev paub txog daim ntawv thov kev sib tham cov ntsiab lus thiab cov cai ntawm cov neeg siv, ua rau nws yog ib qho zoo tshaj plaws platform rau kev tiv thaiv cov neeg rau zaub mov tsis raug cai. Layer 4 switching suav nrog software tsim thiab kev tsim hluav taws xob tsim hluav taws xob.

5. Module redundancy

Redundancy muaj peev xwm yog qhov lav rau kev ua haujlwm nyab xeeb ntawm lub network. Txhua tus neeg tsim khoom tsis tuaj yeem lav tias nws cov khoom yuav tsis poob thaum lub sijhawm ua haujlwm. Lub peev xwm hloov tau sai sai thaum muaj qhov tsis ua haujlwm yog nyob ntawm qhov muaj peev xwm rov ua dua ntawm cov khoom siv. Rau cov keyboards tseem ceeb, cov khoom tseem ceeb yuav tsum muaj peev xwm rov ua dua, xws li kev tswj hwm module redundancy thiab fais fab mov redundancy, thiaj li ua kom lub zog ruaj khov ntawm lub network mus rau qhov loj tshaj plaws.

6. Routing redundancy

Siv HSRP thiab VRRP raws tu qauv kom ntseeg tau tias kev sib koom ua ke thiab kub thaub qab ntawm cov cuab yeej tseem ceeb. Thaum qhov hloov pauv hauv cov tub ntxhais hloov pauv thiab hloov dual-convergence tsis ua haujlwm, peb txheej routing ntaus ntawv thiab lub rooj vag virtual tuaj yeem hloov tau sai sai kom paub txog ob kab rov qab rov qab. Xyuas kom ruaj ntseg ntawm tag nrho lub network.

Peb nyob rau hauv kev kawm nrov:

Lub luag haujlwm tseem ceeb ntawm cov txheej txheem sib sau ua ke ntawm qhov hloov pauv yog raws li hauv qab no:
1. Aggregating cov neeg siv tsheb khiav ntawm cov txheej txheem nkag, ua kom sib sau ua ke, xa mus thiab hloov cov ntaub ntawv xa mus;
2. Ua haujlwm hauv zos routing, filtering, tsheb sib npaug, QoS tswj qhov tseem ceeb, kev ruaj ntseg mechanism, IP chaw nyob hloov dua siab tshiab, tsheb shaping, multicast tswj thiab lwm yam kev ua;
3. Raws li cov txiaj ntsig ua tiav, cov neeg siv tsheb thauj mus los tau xa mus rau cov tub ntxhais hloov txheej txheej lossis xa mus rau hauv zos;
4. Ua kom tiav qhov hloov dua siab tshiab ntawm ntau yam kev cai (xws li cov lus qhia txog kev xa tawm thiab kev xa rov qab, thiab lwm yam), kom ntseeg tau tias cov txheej txheem tseem ceeb txuas mus rau thaj chaw khiav cov txheej txheem sib txawv.