Switch fabric and Backplane in 6500 with Sup 720

cisco_query · ‎10-18-2008

Hi,

Please give reply to my below queries:

1. The normal backplane speed of 6500 series switch is 32Gbps.Is it correct ?

2.The SUP 720 has intergrated Switch Fabric and this increases the 6500 series switch fabric to 720Gbps. Is it correct ?

3. So in 6500 series switch with Sup720 ,can we say its backplane speed is 720Gbps ?

4. How can we see the backplane speed in a 6500 switch ?

5. Each module as 2 fabric channel to crossbar switch fabric intergrated in Sup720 and hence each module gets 40Gbps of backplane speed .Is this correct ?

6. show fabric status ,shows each the fabric channel speed to backplane

Please provide any document that clearly explains all these things.

Thank you

Giuseppe Larosa · ‎10-18-2008

Hello Query,

use the following document about C6500 architecture

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps708/prod_white_paper0900aecd80673385.html

look at the sections

shared bus

Crossbar Switching Fabric

Hope to help

Giuseppe

cisco_query · ‎10-18-2008

Hi,

I already reffered that link and my queries are based on that only . But still I am not clear . If any one has a better understanding on this please give a reply to my queries.

Kindly help.

Thank you

Giuseppe Larosa · ‎10-18-2008

Hello Query,

>> Please provide any document that clearly explains all these things

you have asked a document and you got it

1 )

what you call normal backplane is the shared bus.

2) The SUP 720 has intergrated Switch Fabric and this increases the 6500 series switch fabric to 720Gbps. Is it correct ?

Provides a 720 Gbps CrossBar switching fabric that can be used by new linecards that connect to it (dual connection to switch fabric in all slots in C6509, only on slots 8-13 in C6513)

the shared bus is still there and used by linecards that cannot connect to the crossbar switching fabric

3) So in 6500 series switch with Sup720 ,can we say its backplane speed is 720Gbps ?

No, you can say that a 720 Gbps switching fabric has been added and can be used with specific linecards

4). How can we see the backplane speed in a 6500 switch ?

As stated above in a chassis with Sup720 multiple switching facilities exist so you cannot talk of a single backplane

5) Each module as 2 fabric channel to crossbar switch fabric intergrated in Sup720 and hence each module gets 40Gbps of backplane speed .Is this correct ?

They get a quote of the crossbar switching fabric.

To be noted here numbers are often doubled datasheets count 20 Gbps bidir as 40 Gbps

6) show fabric status ,shows each the fabric channel speed to backplane

to be completed

Hope to help

Giuseppe

Edison Ortiz · ‎10-18-2008

Think of the backplane as a highway and think of the modules are the cars using that highway. If you have a car that can only run up to 40 miles per hour, that's how fast the highway is.

In the 6500 chassis, the backplane speed depends on the module you have inserted in the chassis. If you insert all DFC dual-fabric modules along with a Sup720, then you will achieve the maximum speed of 360Gbps Full Duplex - which in marketing terms equals to 720Gps.

That's 7 modules running at 40Gbps = 280Gbps, with 2 Supervisors also running at 40Gbps = 80Gbps.

If you take a moment, the URL pointed out on this thread contains all the information you may need regarding the 6500 architecture. It's a long read so many people tend to skim thru it without really digging deep into it. It has all the answers for the question you just posted.

HTH,

__

Edison.