Subject: RE: Comments on draft-suping-bfd-mpls-fecmismatch-00.txt

From: "David Allan" <[email-masked]>
Date: Thu, 24 Feb 2005 07:32:28 -0500

Hi Tom:

 <you wrote>
  	The final technical issue I have with the document
 > is that it is based on ITU Y.1713, which is based on
 > ITU recommendation Y.1711. If we take a close look at
 > the scope section of the updated version of Y.1711,
 > we will find that the protocol is limited to
 > connection-oriented network constructs ONLY. For MPLS this 
 > means that it ONLY applies to MPLS-TE LSPs and possibly 
 > things that can ride over those LSPs (i.e.: pseudowires that 
 > use a TE LSP between PEs).  It also means that since Y.1713 
 > is based on Y.1711, it inherits its scoped limitations as well.
 
 This part of the analysis is flawed ....1713 is not limited 
 to P2P, it only uses general PDU design common to 1711. it 
 was designed primarily for LDP but like 1711 had problems 
 with PHP, which in this application would not be an issue. 
 (session ID stunt doubles for the label). 
 
 The FEC filter in 1713 which only needs to be ANDed with the 
 receiver expected value would be very consistent with the 
 minimalist approach in BFD. I had already considered 
 proposing this to eliminate the need for a periodic VCCV-PING 
 to check the control plane binding. And it would be more 
 authoritative than hoping that you did not have collisions in 
 the session discriminator space in conjunction with leakage...
 
 Dave

---

From: "Thomas D. Nadeau" <[email-masked]>
Date: Thu, 24 Feb 2005 10:09:41 -0500

>  the session discriminator space in conjunction with leakage...

	One of my points was that the filter is unnecessary (even if
it would work).  That seems like a more minimalist approach
to me. :P

	--Tom