Re: Question on LMP

[Michiel van Everdingen <MvanEverdingen@lucent.com>]

Hello Jonathan,

Based on the information put forward in this thread, I think some
clarification is needed in the LMP draft.

- Please make clear that "control channels" are established *over*
  a "control network".

- Please make clear that some signaling messages are carried over
  "control channels" and that some signaling messages are carried
  directly over the "control network" (example of the latter: the
  RSVP-TE notify message).

- Add some text on the relationship, configuration dependency between
  RSVP-TE hellos, LMP hellos and the "control network" IGP hellos.
  See http://ops.ietf.org/lists/ccamp/ccamp.2002/msg00655.html.
  This probably causes the need to introduce
  + "signaling channels"
  + "signaling network" / "signaling plane"
  See for definitions of these terms:
  http://ops.ietf.org/lists/ccamp/ccamp.2002/msg00670.html
  http://ops.ietf.org/lists/ccamp/ccamp.2002/msg00725.html

- Add some text to explain why there a (mandatory) need to distinguish
  between a failure of the RSVP-TE process and a failure of the LMP
  process. See
  http://ops.ietf.org/lists/ccamp/ccamp.2002/msg00670.html

- Chapter 1: "To enable communication between nodes for routing,
     signaling, and link management, control channels must be
     established between the node pair ..."
  Please add some explanation why the "control network" is not
  sufficient to enable communication. You could refer to
  http://ops.ietf.org/lists/ccamp/ccamp.2002/msg00725.html

- Chapter 2: "... the control channel MUST terminate on the same
     two nodes that the TE link spans"
  Please add an explanation on exactly what is meant here. Compare
  e.g. LSP termination (in which an MPLS label is terminated/removed),
  TCP termination (in which the TCP header is terminated/removed) and
  STS-1 termination (in which STS-1 line overhead is terminated/
  removed). What is terminated/removed at the end of a control
  channel ?

- Chapter 3: "The LMP Hello protocol is intended to be a lightweight 
     keep-alive mechanism that will react to control channel failures 
     rapidly so that IGP Hellos are not lost and the associated link-
     state adjacencies are not removed unnecessarily."
  Please be precise on what IGP is meant here; the IGP of which plane/
  network ? The control plane, the signaling plane or the transmission
  plane ?



Thanks !

Michiel


-- 
+------------------------------------------------------------------+
| Michiel van Everdingen                                           |
| Systems Engineer                                                 |
| Lucent Technologies - Optical Networking Group                   |
| Botterstraat 45, 1271 XL       Phone : +31 35 687 4883           |
| P.O. Box 18, 1270 AA           Fax   : +31 35 687 5976           |
| Huizen, The Netherlands        mailto:MvanEverdingen@lucent.com  |
+------------------------------------------------------------------+