Re: Last Call on RSVP Label Allocation for Backup Tunnels

[Robert Raszuk <raszuk@cisco.com>]

Hi Neil,

> > If one questions the use of local protection all together
> > please specify
> > how else you will achive the same results of even less then 1
> > sec end to
> > end traffic disruption with end to end protection under both
> > link & node
> > failures for the TE- LSP ?
>
> NH=> Fair point Robert.....but it still leaves me wondering:
> 1       Why do we need such fast action......voice surely does not need few
> 10s ms restoration, 1-3s would be fine I feel sure (for the relatively rare
> case of failure......unless, perhaps, one expects such failures to occur on
> a very frequent basis)?
> BTW- I suspect the biggest source of 'disruptions' will be planned-works by
> operators at L1, ie pre-meditiated re-routing of traffic.....so some care
> should be taken that such actions don't invoke unecessary actions in higher
> layers.

Well 10s of ms is just that with local link protection we get it for
free. It would be quite artificial to try to slow this down :). For node
protection sure one can reduce the detection frequency to make it
slower. I think vendors will support knob to do this if one desire.

> 2       Where are the failures referenced specified?  Have Cisco their own
> specifications for this?  We would really like to see these specified in
> some standard manner.

I understand but I don't have any pointer to the formal detailed
specification of failure cases which would be addressed by local
protection. 

R.