-----Original Message----- From: Alex Rubenstein [mailto:alex@nac.net]
On the 7500, you have RSPs and VIPs; the former performing routing protocol work, vty's, RIB's, etc., the latter doing actually packet forwarding.
While this sounds great on paper, our experience has us shying away from dCEF and looking for something bigger and better... dCEF pushed the RSP processor down to about 5%, but pushed up the VIP processors to about 90-95%...
VIP-Slot0>sh proc c CPU utilization for five seconds: 13%/12%; one minute: 14%; five minutes: 15%
I wish we could get our routers to do this...
Obviously, we run dCEF, which puts the VIP's in the position of forwarding everything on their own, as evidenced by the CPU measurements.
But each VIP is responsible for it's own traffic, so if a particular VIP runs most of the traffic, it has much higher CPU usage... In our case, we have a router loaded with VIP 4-50's and Enhanced ATM OC-3 adapters... Originally, we had a single OC-3 running about 120-130 Megs constant and the VIP CPU was at 90-95%.... To combat this, we had to put in additional OC-3 cards with additional VIPs and distribute the load... Still, high CPU is a problem .. For instance : CPU utilization for five seconds: 63%/63%; one minute: 63%; five minutes: 65% 30 second input rate 78227000 bits/sec, 17858 packets/sec 30 second output rate 47944000 bits/sec, 12778 packets/sec It seems to me that we should be able to do sooo much better... *sigh* OC-12 adapters are an option, but they are rather expensive ...
However, to answer your question, even a modestly configured 7507 with RSP4, and VIP2-50's will be substantially more capable than a 7206-NPE300. Things may change on the NPE-400 or G1, but I have no direct experience with that.
The G1 processors, so far, have proven to be wonderful... We only have experience with them running in the 7200 uBR chassis, but they've shown a huge reduction in CPU utilization...
PS. Regards to stability; we have SUBSTANTIAL improvements in IOS stability, especially in 12.3.5a mainline.
Heh.. *old* Cisco code scares me enough... Bleeding edge is simply terrifying... *sigh*
-- Alex Rubenstein, AR97, K2AHR, alex@nac.net, latency, Al Reuben -- -- Net Access Corporation, 800-NET-ME-36, http://www.nac.net --
Jason Frisvold Backbone Engineering Supervisor Penteledata