opinions on routers/switches for parallel clusters

[keichii () freebsd org]

Hi Everyone,

We are an educational institution looking into building 
a scientific computing cluster that has 128-256 nodes 
interconnected by gigE.  The outward connection would
be the site FDDI ring.

The problem is that we want to experiment with the topology
as well as the computing part. :)  And I am at a loss
as to what gigE switch and router we should use.

The requirements are:
1. ability to morph the topology at will
2. fast (doh!)
3. Layer 1-4 is required (up to layer 7 would be nice)
4. load balancing

Which companies' products do you like? (*Barring* Cisco)
[If you cannot state your opinion publicly, please send me a 
private reply.  I appreciate it and will keep it confidential.)

I am looking at these companies:
Lucent
Foundey Networks
River Stone
Alteon
Extreme Networks
Ericcson

Would the people who have had experience with these products
tell me what they feel?  Thank you very much.

Michael
-- 
+-----------------------------------------------------------+
| keichii () iteration net         | keichii () freebsd org       |
| http://iteration.net/~keichii | Yes, BSD is a conspiracy. |
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