Open Source BGP-router?

Jim Shankland nanog at
Thu Dec 6 16:32:19 UTC 2001

Does anybody have any rough figures for what kind of load (both
bytes/s total throughput and packets/s) a more or less vanilla x86
running a free OS can handle today?  The last time I looked at this --
several years ago -- I seemed to top out at somewhere close to 200
Mb/s total throughput; I figured I could safely count on 100 Mb/s.
That is consistent with a 32-bit PCI bus running at 33 MHz: raw
capacity is 1 Gb/s, but each bit takes two trips over the bus, so
that's 500 Mb/s, but then there's substantial bus overhead
(contention, burst setup overhead, etc.).

I didn't look at packet count limits, as they didn't seem to be
a problem for me in my actual traffic mix; but I expect that with
enough small packets, packet count would become the limiting factor.

That was in the days when a Pentium 133 was a mid-range PC.  I would
expect faster memories, bigger caches, but (most of all) a 64-bit
PCI bus running at 66 MHz to make a big difference.

Hypothetically, a box that could handle, say, 750 Mb/s is not suitable
for "core" use, but it can certainly handle more than "a couple of

Jim Shankland

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