innocent remark

Dennis Ferguson dennis at
Thu Apr 28 00:35:10 UTC 1994

> given that a BSD/386 or NetBSD system can be put together quite cheaply and
> does a fine job at handling PPP and SLIP and multiple ethernets, this seems
> like a fine alternative to dedicated routers like Cisco for T1/E1-speed
> internet gateways.  especially considering the power of GateD 3.5, and that
> a 16MB cisco can't handle a "full internet route table" while a 16MB i486
> machine can do it easily.

The end of the last sentence is wrong (the start of the last sentence
might be too, though I'm biased enough to maybe believe it).  I know
for a fact that, while gated's memory usage is not unreasonable, gated
code does tend to resolve memory/CPU tradeoffs in favour of spending
memory and saving CPU.  And the per-route memory consumption in the
Net/II kernel forwarding table is way out of line with what a decent
router implementation should do.  If you want your 486 box to compete
with a 16MB cisco you really need to buy it a couple of extra rows of
SIMMs.  By the time you get enough neighbours and alternate paths in
there to overwhelm a 16MB Cisco the 16MB 486 box will be spending most
of its time trying to get large chunks of gated into and out of the
page space, though a 32MB 486 box should still be pretty chipper.

My (somewhat dated) observation is that i486 machines also seem to do
a whole lot of work to get quite mediocre packet-per-second forwarding
rates.  On the other hand, if you buy it a good screen and interface card,
the graphics are much better than even a 64MB Cisco.

Dennis Ferguson

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