SUP720 vs. SUP32

Holmes,David A dholmes at
Wed Mar 18 17:01:41 UTC 2009

Important network design parameters to take into consideration when
planning SUP720 vs SUP32:

1. SUP720 has 720 Gb backplane (switchfabric) on supervisor card, and 32
Gb shared bus backplane.
2. SUP32 only has 32 Gb shared bus backplane
3. New Cisco line cards with dual 20 Gb connections to 720 Gb backplane
only work in the SUP720, and some only in IOS version (such as the 16
port 10 GiGE line cards)
4. Older line cards that work with SUP32 have relatively small shared
hardware buffers for every 8 ports, such that it is possible to run line
rate through one port and cause drops on the other 7 ports
5. Cisco recommends SUP32 for the wiring closet, as a desktop
aggregation device 

-----Original Message-----
From: Norrie, David [mailto:David.Norrie at] 
Sent: Wednesday, March 18, 2009 9:48 AM
To: Adrian Chadd; Bill Blackford
Cc: nanog at
Subject: RE: SUP720 vs. SUP32


I have been searching cisco-nsp archive but not been able to find the
article discussed below. I would appreciate it if someone does find the
article if they can provide a copy/link to this :

> Check the cisco-nsp archive, specifically from Rodney; he has talked
about what the 
> CPU load versus throughput implications are on the G1 and G2. It might
surprise you a 
> little.


More information about the NANOG mailing list