On Jul 9, 17:57, "Daniel W. McRobb" <dwm@ans.net> wrote:
The sampling Curtis mentioned on the NSS routers is a bit different. For one, it doesn't really impact forwarding performance (and hopefully, if/when implemented on the Bay, will not impact forwarding performance).
Not to pick nits, but what I quoted was a cache snapshot; caches don't impact performance under normal circumstances, though their construction may do so.
But what we're specifically looking for in terms of continuous sampling (such as that we do on the NSS routers) is a net matrix... if you changed the Cisco flow switching stuff to use network numbers (and mask), you'd have something very much like what we're looking for in terms of continuous sampling. From there we build AS matrices, etc.
Yes ... but you shouldn't need anything special for that. We have been doing the same for a long time, using regular IP accounting on the edge routers, which is then summarised over a full routing table. The only discrepancies that occur are if changes in routing occur between the time of accounting and processing, but this tends not to be a problem.
The other thing about the flow-switching data that's different than the NSS (and probably what we'll get from Bay) is that there aren't really any nice ways of retrieving/storing the data automatically.
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