Gigabit copper networking and Cisco gear

[Pete Wyckoff]

Justin.Baker at csiro.au said:
> The most suitable Cisco switches for a cluster of this size look like
> the 10+2 port 3550 or the 8 port 3508G.
[...]
> Can anyone give me an idea why these switches don't seem to be used
> for clusters?

I just happen to have recently measured the basic parameters on a few
switches found lying around here.  The 12-port fiber gigabit ethernet
Cisco 3550 is lousy by comparison to the Extreme 6816 or even ancient
Packet Engines repeater.

http://www.osc.edu/~pw/emp/switch.html

Be aware that other factors such as bisection bandwidth and feature set
may be important as well.  I just happen to care primarily about layer 2
forwarding delay at the moment.  And, yes, better throughput numbers can
be obtained by playing around with host TCP settings.  These
measurements just show switch differences (1500-byte MTU and factory
default configuration).

Foundry and Force10 have dense gigE at perhaps reasonable prices but I
have not seen performance numbers.

This in case the "cost" argument wasn't enough to convince you.  :)

		-- Pete