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Re: Access to the Internic Blocked
 From: Vadim Antonov
 Date: Mon Aug 26 18:03:02 1996
Daniel W. McRobb <dwm@ans.net> wrote:
> >12 million is not much. Even in the NSFNET days, I worked w/
> >5millioncell net matrices. All it takes is memory and some CPU.
>
> 12 _simultaneoulsy_, not over period of time. The 1hr matrix
> would be two orders of magnitude bigger.
>A typical 1 hour matrix is considerably smaller. Even a core router
>who carries 40,000 routes will not see anywhere near 40,000 * 40,000
>cells in a one hour period, or even 2 million cells. Not in my
>experience. Even the NAP and MAE routers where I've collected this data
>have seen net matrices only on the order of (10^3) to (10^5) for a one
>hour period.
That's _host address_ matrix, not network address matrix. It is at least
three orders of magnitude bigger.
Another datum  the hot spot on route cache on ICM's routers from
hell is about 40% on networks addresses.
>The number of cell entries is not equal to the number of routes squared.
>It doesn't happen.
No, nobody said that. That's why my figures are in 100M range, not
2000000 bil which is the size of "full host matrix".
>Even if your router is expiring 20,000 flows per second,
>it only comes out to about 667 packets per second to the workstation,
>which is pretty low even for older workstations with fairly weak CPUs by
>modern standards. An Alpha can handle it w/o even breaking a sweat.
20k flows per second? You must be kidding. The average flow length
(as derived from Sean's stats) is 20 packets. I.e. 20 kfps is what
you get from a single OC3 working at the wire speed.
vadim
                
