On Jul 13, 2010, at 12:11 PM, Yaakov Stein wrote: > 2) Why do we need a new encap. Why not just use the UDP/IP one and put it in > MPLS, or the Ethernet one in a PW. > Of course it is fine to carry 1588 inside UDP/IP or Ethernet inside MPLS. > For that matter you can put the 1588 in Ethernet inside an Ethernet PW inside > IP (using RFC 4023) inside MPLS, > and many other encaps. The problem is the predictability of finding the > fields inside. > > When you say 1588 in Ethernet encap, is that untagged ? 1 VLAN tag ? 2 tags ? > MAC-in-MAC ? > In UDP/IP is that without IP options ? > > The idea behind defining another transport layer (and, incidentally, there > are already more defined in 1588) > > We COULD standardize one of these (e.g., never tagged), > but what would we do in a hybrid scenario when it comes in from Ethernet with > a tag ?
My experience suggests that operators will do whatever minimizes their operational complexity. This implies that if they are running a IP over MPLS network today, that they will use an IP encapsulation. If they are running a primarily PW over MPLS network today, they will run PTP over PW. In short, we will have to deal with _all_ of these encapsulations already. Defining a new one only makes the problem larger, and it's of dubious value as most providers will not want to assign labels simply for PTP. My $.03, Tony _______________________________________________ TICTOC mailing list [email protected] https://www.ietf.org/mailman/listinfo/tictoc
