Sup 720 Fabric questions

[nathan.deane]

Hi,

If you use a 6509-E with a Sup 720 this gives you a 720 Aggregate switch fabric which is broken down across all of teh 9 slots. However each slot only has 2 x 20 Gbps interfaces, so if you plugged in a 48 10/100/1000 you will not be able to get the full 48 Gbps throughput.

I know it is probably impossible to generate so much traffic but i am curious as the modules are marketed as non-blocking?

does anybody have some infor on this

Thanks

[Roberto Salazar · Accepted solution]

Fabric channels run at 20 Gbps Full Duplex, so 20 Gbps in / 20 Gbps out, so the claim is 40 Gbps in full duplex and 80 Gbps/slot with dual fabric channels

Search for 80 Gbps:

http://www.cisco.com/en/US/products/hw/modules/ps4835/products_data_sheet09186a00801dce34.html

[nathan.deane]

Of course

That actually makes perfect sense now

thanks a bunch !!

[nathan.deane]

Actually....

if Full Duplex is in the question then a 48 x 1000 Mbps would need 96 Gbps not 80 ??

[glen.grant]

I believe this only applies if you are running fabric enabled cards like dfc3's , if you are running older cards this thruput doesn not apply .

[nathan.deane]

Even if the card is fabric enabled with 48 x 1000 Mbps ports you still only have 2 x 20 Gbps connections for each module

+(i have just found out) access to the shared 32 Gbps Bus