RE : RE : RE : Last call comments: draft-ietf-tewg-interarea-mpls-te-req-01.txt
"LE ROUX Jean-Louis FTRD/DAC/LAN" <[email protected]> Fri, 18 Jun 2004 15:49:56 +0200
| Newsgroups | gmane.ietf.ccamp,gmane.ietf.tewg |
|---|---|
| Message-ID | <D109C8C97C15294495117745780657AE2BA646@ftrdmel1.rd.francetelecom.fr> |
Hi Arthi Please see inline Regards, JL >> >As I explained in my email to JP, it is still somewhat=20 >unclear as to=20 >> >what the ability to signal the desired method buys the=20 >provider, and=20 >> >exactly why or how that simplifies LSP management. >> >> Basically, as mentionned by JP, the signaling method used=20 >will have a=20 >> non negligeable impact on important features (Reoptimization, FRR,=20 >> rerouting). For instance, if you use sitching or nesting, you will=20 >> face FRR issues as regards ABR protection. >----------> Let me try to explain this, if possible with a couple of >examples: >Re-optimization >--------------- >Actually, nothing prevents you from having Head-end Control of=20 >re-optimzation even with the non-contiguous signaling methods.=20 >It is just that with the non-contiguous signaling methods, one=20 >can, if desired, also have the ability to do a local=20 >re-optimization. But if you do not want this 'intermediate=20 >re-optimization' behavior for certain LSPs, you may want to=20 >signal that explicitly or configure it on the box. Agree > >Crankback/Re-routing >--------------------- >The crankback document actually provides a similar ability for=20 >controlling re-routing at intermediate nodes by signaling this=20 >explicitly. Agree, And what about FRR: if I want FRR protection of ABRs with no impact on backup length and recovery delay, I definitely need contiguous LSPs. This is actually the only signaling mode allowing this service. Thus I prefer to signal directly the signaling mode "Contiguous LSP", rather than the required service, in order to avoid any misinterpretation of this service ...