Mark, > Please see inline.
in-line... > >>>>>>>>i heard there is a way to run MPLS for layer3 VPN(2547) > >>>>>>>>service without needing to run label switching in the > >>>>>>>>core(LDP/TDP/RSVP) but straight IP (aka iMPLS). > >>>>>> > >>>>>> ftp://ftp.ietf.org/internet-drafts/draft-townsley-l2tpv3-mpls-0 1.txt > >>>>>> > >>>>>> See also Mark's talk from the last NANOG > >>>>>> > >>>>>> http://nanog.org/mtg-0402/townsley.html > >>>>> > >>>>>That requires to run L2TP. An alternative is to run GRE (or even plain > >>>>>IP). The latter (GRE) is implemented by quite a few vendors (and is > >>>>>known to be interoperable among multiple vendors). > >> > >>The only multi-vendor interoperable mode of GRE that I am aware of requires > >>manual provisioning of point-to-point GRE tunnels between MPLS networks and > >>to each and every IP-only reachable PE. > > > > > > I guess you are *not* aware of the Redback implementation of 2547 > > over GRE, as this implementation is (a) available today, (b) > > interoperable with other implementations of 2547 over GRE, and (c) > > does *not* require manual provisioning of point-to-point GRE tunnels > > between MPLS networks and to each and every IP-only reachable PE. > > > > And, just for the record, (stating the obvious) I don't work for Redback. > > Are you referring to draft-raggarwa-ppvpn-tunnel-encap-sig-03.txt? (Just > guessing as the principal author used to work for Redback). Thanks for the > update, I was in fact not aware that companies other than Redback had > implemented it. You didn't name those companies, but I will happily stand > corrected here. No, I was *not* referring to draft-raggarwa-ppvpn-tunnel-encap-sig-03.txt. Redback's implementation that does not require manual provisioning of point-to-point GRE tunnels between MPLS networks and to each and every IP-only reachable PE is *purely* an implementation matter, and does *not* require any new communities and/or attributes. > In any case, the point I was trying to make was that there is more than > one way to do "MPLS over GRE" and that they are not all necessarily > interoperable as you seemed to imply in your message. You have helped > to make that quite clear. > > >>The BGP extension defined in the draft below allows "iMPLS" for 2547 > >>VPN support without requiring any manually provisioned tunnels (and > >>works for "mGRE" or L2TPv3). > >> > >>http://www.watersprings.org/pub/id/draft-nalawade-kapoor-tunnel-safi-01.txt > > > > The question to ask is whether the extension you mentioned above is > > truly necessary for supporting 2547 over GRE. The Redback implementation > > I mentioned above is an existence proof that the extension is *not* > > necessary for 2547 over GRE that does *not* involve manually provisioned > > GRE tunnels. > > Both draft-nalawade-kapoor-tunnel-safi-01.txt and > draft-raggarwa-ppvpn-tunnel-encap-sig-03.txt use BGP to advertise capabilities > for carrying MPLS-labeled packets over various encapsulation types. Proof of And *neither* of these are requires in order to avoid manual provisioning of point-to-point GRE tunnels. Yakov.
