nanog mailing list archives

Re: SONET ring questions


From: Alex Bligh <amb () gxn net>
Date: Fri, 16 Oct 1998 10:55:57 +0100


1) Bell Atlantic assures us that, because of the redundancy, we can
   expect 100% uptime from the OC-12.  I would like feedback as to 
   whether this is a realistic portrayal of the SONET environment.

Don't just buy from one carrier. Even if they give you dig plans,
and diversity warranties, they are likely to reroute things without
telling you. Even if you get around this one, and all the other problems,
and are satisfied you have permanent, true, diversity which will protect
you against any one fiber break, it doesn't protect you against a
procedure break, like someone terminating the wrong circuit on misreading
a circuit ID.

The above is certainly true in the UK, and from my experience in the US
I'd think it's doubly or quadruply true.

Also, use the lowest level routing redundancy you can find. I may get flamed
for this, but if bandwidth is not an issue, you might consider ATM switches
instead especially if cutover time is critical.

-- 
Alex Bligh
GX Networks (formerly Xara Networks)




Current thread: