SUP720 vs. SUP32

Anyone have any experience with SUP32? Please contact me off list.

I'm trying to evaluate a lower-cost alternative to the 720-3bxl.
I'm only pushing a few hundred megs of traffic, exchanging a few routes with less than 20 peers and don't see the need for a 720's worth of throughput in the near future.

Can the 32 handle a full table?
How does the MFSC2A compare to the MFSC3?
V6 support?

Thank you.

Start here:


Honestly, my advise is don't handle full tables in switches unless you want to use 3bxl. Use routers, any old ISR can do 1GB memory or so and handle the table just fine, and run you a fraction of the cost. Keep internal routes, defaults, etc in the switching core.


No...not unless things have changed and you can get/put a pfc 3bxl on a sup32.

Actually let me amend that and say 3800's as far as inexpensive routers. They are basically NPE400 class devices, with alot of memory and sufficient to handle the full table. Other router devices like 7200's etc will work fine as well.

Thank you to everyone who offered advice. I thinks it's clearer what my path should be.

Incidentally, I am using 7300/7200 based units with G1 RP and found that at 200M they start seeing 50% CPU load which is why I'm looking to go to the next step.

Again, thanks to all


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.


Make sure that the new 10 GiGE line cards are not in your plans if you
choose the SUP32. This holds for some of the other copper and fiber line
cards where line card buffer capacity may be critical to effective
throughput. Some new line cards only connect to the 720 Gig backplane.


As far as pricing for refurbished Cisco Supervisor Engines the 3BXL is
selling for around $7500 whereas the WS-SUP32-10GE-3B $5500, WS-SUP32-GE-3B

Best regards,

Larry E. Stites
Northern California Networks, Inc.
LIC# 2004 SR KH 100-484111
Nevada City, CA 95959

Be sure to optimize your configuration before you upgrade.
Depending on what services you have enabled (either by
default or design), you can squeeze quite a bit from these
boxes before you need to upgrade with a pretty lean
configuration - and the NPE-G2 can sit a sweet 2GB of DRAM
nicely :-).

We've been able to forward some 950Mbps out of an NPE-G2 at
~72% CPU utilization as a core router, and about 600Mbps at
the same CPU utilization as an edge router.

With the current bloat of the routing table today, the sheer
force software routers provide re: RIB/FIB memory for a
couple-of-hundred Mbps of traffic forwarded is hard to




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



(First hit from googling "c-nsp rodney dunn NPE-G2 CPU")

Make sure you read all the posts in the thread, the figures Rodney gives
need some further explanation.


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