[39846] in North American Network Operators' Group
SONET UPSR questions
daemon@ATHENA.MIT.EDU (Rishi Grover)
Wed Jul 25 14:21:30 2001
Message-ID: <0B38BC6A6966D411A1EE00D0B774D70242E6B6@rwnms1.redwavenet.com>
From: Rishi Grover <rgrover@redwavenet.com>
To: nanog@nanog.org, "'nanog@merit.edu'" <nanog@merit.edu>
Date: Wed, 25 Jul 2001 11:25:55 -0700
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Hi,
I don't know if this is the right forum but if someone could
shed some light on the following questions, I would really
appreciate that. I have read the standards but did not get
a clear understanding on the following:
1) Given a SONET ring with UPSR, is it required that all working
paths be in one direction (clockwise or anticlockwise) and all
protected paths be in the opposite direction? Can I provision
some working paths to be clockwise and some to be counterclockwise?
I couldn't find anything in the standards that says that this is not
allowed.
If this can be done, what are the merits/demerits of this approach?
2) In UPSR, when provisioning a working path, my understanding is that
it is not "required" to provision the protected path as well. i.e. One
can provision only unprotected paths in a UPSR configuration. Is this
correct?
3) Given a deployment of 4 node UPSR configuration A, B, C, D.
Say I provision a working path in clockwise direction from node A to D. Say
I
am using timeslot 'x' for this path. Is timeslot 'x' also reserved in the
clockwise
direction from D to A?
What is the rational behind reserving this timeslot 'x' from D to A?
Thanks,
Rishi
