Gigabit copper networking and Cisco gear

Pete Wyckoff pw at
Mon Oct 21 06:47:12 PDT 2002

Justin.Baker at 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.

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

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