Thank you for reading. I have a 2811 with an NM-1T3/E3. I know it can't support a full T3 but does anyone know if I can get away with using this on a 15Mb partial DS3? This is just temporary. Cisco only says it supports it "Subrate T3/E3 with concurrent services" but doesn't specify what that subrate is.
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Process switching means, for some reason, the packet needed to be handled by a complex set (i.e. slow) set of code on the router. CEF/Fast switching, means the packet was able to be forwarded by some very optimized code. All packet forwarding on a 2811 involves using software, but how the code does what it does can sometimes have huge performance implications.
Enabling CEF does not guarantee all packets will be CEF switched (just hopefully most).
The 61.44 is a measure of how fast that system's CPU can make a L3 forwarding decision for a L3 packet. Real packet forwarding involves more overhead, sometimes much, much more overhead, and the CPU has other "stuff" to process too (e.g. keeping all the stats current).
I'm attaching a later ISR performance document. It doesn't cover the 2800 series, but take note the difference between raw performance metrics at the beginning of the document and recommended performance usage at the end of the document. You should see quite a difference.