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Paolo Bevilacqua wrote:
However, your NPE-400 can probably deal with 130 Mbps.
Hardly. I was in the Cisco testing team for the NPE-400 when introduced, and it did just what it was labelled about, 400 Mbps uni-directional under ideal conditions. Not 130 bi-dir in real world.
Paolo, I thought the 400 was its KPPS rating, no?
You're saying initial introduction testing showed ideal conditions 400 Mbps unidirectional (or 200 Mbps bidirectional?) yet it couldn't support real-world 130 Mbps bidirectional, correct?
This initial testing was pre-CEF? Also pre-TurboACL and perhaps other features moved to fast path? No real-world traffic forwarding improvement since device introduction?
How I figured: I assumed that 400 does represent KPPS for 64 byte packets (which seems to be the case looking at the attached Cisco router performance sheet) and allowing for all minimum size Ethernet packets, which requires 148.8 Kpps per 100 Mbps, and doubling for duplex and allowing for 130 Mbps, requires 386.88 Kpps. Of course this is (too) close to 100%, and CPU will be also be consumed by other configuration options, but generally "real" traffic isn't all minimum size packets. (I.e. I would expect real-world CPU demand to be at least half of all minimum size packets.)
This is why I wrote ". . . your NPE-400 can probably deal with 130 Mbps.", at least according Cisco published specs.
Paolo since you did work for Cisco, are these specifications inaccurate?
Paolo, what am I missing in my thinking, above? Are you sure the NPE-400 would be inadequate? If so, could you clarify why?
PS:
In one of Zeek's later posts, he notes PA-GE and NPE-G1 about the same price (implying he doesn't have any 7200 gig ports). For the same (or nearly the same) price, the NPE-G1 would clearly be a better choice.
