Subject: [mpls-tp] MPLS-TP Ring Protection

From: "Sprecher, Nurit (NSN - IL/Hod HaSharon)" <[email-masked]>
Date: Thu, 25 Mar 2010 21:40:27 +0100

Hi,

As per my comment that I did have the chance to express.......

The draft that was presented by Yaacov, is an applicability document
indicating how we can use existing mechanisms and constructs in an
optimal way to comply with the requirements presented in RFC 5654 and
satisfy the optimization criteria expressed in RFC5654. This also ensure
interoperability and compatibility especially in inter-ring
scenarios.....

We also got a lot of positive feedbacks from SPs and vendors which
second this approach......

We need good justifications to define a new mechanism..........

In your slot, you mentioned that the main difference from FRR mechanism
is that in FRR there is a need to differentiate between node and link
protection........that is correct, but in FRR we can have a single
bypass tunnel to bypass a link failure and a single one to bypass a node
failure.......where each bypass tunnel aggregates all the protected LSPs
that transmit over the protected facility..........this of course can be
achieve also with Linear protection.....using PST.  Does this justify a
definition of new mechanism?

Also, it is not clear that wrapping is the best
construct.........(requires better planning of the resource allocation,
traffic require double bandwidth for the segment between the neighboring
node until the egress, may incur added latency (that increases for
larger rings) to message delivery.etc.

we can have steering and as defined in the draft that Yaacov presented
turn ring into a lower layer protected span, by using PST protection. 

The draft that Yaacov presented supports both wrapping and steering
constructs.....which are implemented in an optimal way.....it supports
p2p, p2mp, 1:1, 1+1.....

We need a good justification to develop a new technology.......

You mentioned that you have a lot of support from SPs to your proposal.
Can we get more feedback from those SPs why they prefer these approach
and look for a new mechanism and why they prefer using the wrapping
mechanism., 

Best regards,

Nurit