[4178] in North American Network Operators' Group
Re: Optical bypass switches (Re: MAE-East still no generator)
daemon@ATHENA.MIT.EDU (Dave Curado)
Sun Sep 8 19:04:18 1996
Date: Sun, 8 Sep 1996 19:09:19 -0400
From: Dave Curado <dcurado@neteng.nis.newscorp.com>
To: SEAN@SDG.DRA.COM
Cc: nanog@merit.edu
> A thought I just had. How many folks have optical bypass switches on
> their fddi connections? If a enough providers' equipment fail without
> bypassing, the ring can get partitioned into different sections which
> might explain some of this. Supposedly DRA's router is plugged into
> the gigaswitch, but I don't have a gigaswitch manual to check what
> happens with ring partitions.
Perhaps we're getting off of the nanog topical area here, but...
To the best of my knowledge, the fddi ring at mae-east is a
concentrator type ring, a to m / b to m type of thing... instead
of a fddi trunk type of ring with a to b and b to a.
MFS may have a number of concentrators hanging off of the Gigaswitch.
One of the nice things about a concentrated ring, if you will, is
that individual ports can come up and down... the ring transitions,
but when a node or nodes go down, the ring doesn't partition.
One note of humor about optical bypasses... although I've never used
them, I'm told they're less reliable than most fddi cards -- they end
up breaking and causing more problems then if you lived without them. =-)
davec
