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RSVP fallback ?


I have a fully meshed network WAN consisting of 4 routers on which I want to run VoIP from directly connected PBX. Bandwidth is not sufficient to transport all my VoIP traffic in case of link failure. I'm planning to use RSVP for that purpose but want to know the following :

With RSVP, if the bandwidth on a path is not able to accept a new call, does RSVP will fallback to the next route (from the IP routing table) and try to place the call on this ? Same question if instead I have a second dial-peer with the same destination pattern with a higher preference...does RSVP will fallback to this second dial-peer ?




Re: RSVP fallback ?

To the best of my knowledge, fallback will happen in your scenario.

New Member

Re: RSVP fallback ?

Peter...From what I can gather from your post, the following applies.

RSVP will use the current IGP route and attempt to make a reservation. If current resources are unable to support the request the endpoint that made the request (in this case probably an h323 gateway) will get a path error and the 'call processing agent' (probably the same h323 gateway NOT the PBX) will have to rely on the next dial-peer, utilizing either diffserv, best effort, or the PSTN. RSVP itself will not fallback to anything on its own!

There are some appliances out there that can not only request the RSVP path as a proxy on behalf of the telephony endpoints (or gateway), but can also aggregate multiple flows over a single RSVP path, AND can engineer a preffered path over that of the current IGP path!

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