The MPLS WG Archive

[Adrian Farrel <AF@dataconnection.com>]

>>Note that whether intermediate nodes process the message is a 
>>distinct issue from whether the message traces the LSP 
>>hop-by-hop or goes along a completely different path.
>
>Care to elaborate on the importance of this issue?

Lou,
I just want to separate the discussions.

I don't think it is a big deal if every LSR on the path of a Notify passes
the message through software.  I just think it a shame not to offer the
facility for a switch to fast-path the message (i.e. not remove it from
forwarding hardware) if it is capable.  Thus I would be happy with Notify
targeted at some remote node and router alert NOT set.  It is then up to the
individual switch how optimally it processes the packets.

I believe it is important to allow a Notify to not retrace the path of the
LSP.  This allows a Notify to be routed around a fialure (2nd order failure
- so perhaps not too important).  It also allows a Notify to be sent to some
other entirely distinct node (widening the purpose of Notify from simple
protection switching).

Adrian