[c-nsp] Resilience in order of few hundreds of milliseconds

[Aaron Daubman]

Alaerte,

> When there is FRR support, we can use RSVP hellos; I am wondering way
> Cisco does not support RSVP hellos being a mechanism to indicate failure
> on logical tunnel interface from headend to tailend. The headend would
> detect failure on option 1 and try option 2. (or if there are two tunnel
> interfaces with diverse path and Multipath Routing, when one logical
> interface goes Down traffic would be carried by other interface)
> Any comments?

Might MPLS TE Path Protection be what you are looking for?
http://www.cisco.com/en/US/products/sw/iosswrel/ps1829/products_feature_guide09186a0080333d0d.html

IIRC, path failure can (and generally will) be indicated to the
head-end by both the IGP as well as RSVP messaging (although I cannot
now locate the reference I found that explicitly stated this, it did
mention that one's configuration and network details would determine
whether the headend would receive the IGP or RSVP update first...).
Perhaps somebody can confirm if this is how Cisco's MPLS Path
Protection is implemented?

Regards,
     ~Aaron