[c-nsp] Cisco Router IRB

[Mikael Abrahamsson]

On Mon, 5 Mar 2018, Arie Vayner wrote:

> My gut feeling tells me the performance will be the same for irb and 
> regular routing. These are software routers, so the performance depends 
> on how many and which features you enable.

There is a huge performance difference (at least in older routers and 
older software) between CEF-enabled forwarding paths and non-CEF-enabled 
forwarding paths, even on CPU based routers.

Look for routerperformance.pdf and compare "process switching" and 
"fast/CEF switching". There is often 5-20x difference in pps. So at least 
back then it was important to use features that were CEF enabled, 
otherwise performance would go down a lot.

-- 
Mikael Abrahamsson    email: swmike at swm.pp.se