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Re: [Idr] draft-asati-idr-bgp-bestpath-selection-criteria as IDR WG draft

Ilya,
Are you really recommending that each application (one of them being BGP) which may use underlying transport of LSPs to continuously perform it's own OAM check over such LSPs ?
I really think it is a data plane OAM thing which should be done in full abstraction to routing protocols or label distribution protocols before such LSP is inserted in RIB as a means to reach destination XYZ. 

Cheers,
R.


-----Ursprüngliche Nachricht-----
Von: idr-bounces at ietf.org [mailto:idr-bounces at ietf.org] Im Auftrag von Robert Raszuk 
Gesendet: Donnerstag, 23. Juli 2009 09:13
An: curtis at occnc.com
Cc: idr List
Betreff: Re: [Idr] draft-asati-idr-bgp-bestpath-selection-criteria as IDR WG draft 

Hi Curtis,
I think your assessment of the draft is right. The original issue has been raised by the problem of considering next hop as valid and reachable IP reachability wise without any correlation with MPLS LSP to such next hop which was a must and a prerequisite for some applications to work. 

In my opinion this is a valid problem, but this is not a BGP issue.
Underlying transport (for example MPLS LDP or MPLS-TE) should only expose valid and reachable LSPs to it's RIB so when BGP 

Robert,

in some scenarios (e.g Inter-AS MPLS stuff) labels are distributed by BGP itself. Also, LDP may have received all correct info from the neighbors, but failed to install it into forwarding plane (either due to hardware failure or a software bug). Having experienced this with routers from two different manufacturers, I believe it would be really benefical if BGP could perform a bit more extended checks rather than just looking into control plane. I understand that issue is more of "local type" (e.g. hardware failure) rather than protocol itself, but considering reality (bugs do happen and hardware does fail) it's very desirable that BGP specs at least encourage implementors to make more effort in validating next-hop. And this is why I believe IDR is correct WG for this draft.

Cheers,
iLya