RE: Question: purpose of LMP ChannelActive message (was relations hip of RSVP-TE and LMP)

[Jonathan Lang <[e-mail]>]

George,
  Sorry, I missed this one.  See inline.

-Jonathan

> -----Original Message-----
> From: George Young [mailto:[e-mail]]
> Sent: Tuesday, September 18, 2001 6:05 AM
> To: [e-mail]
> Subject: Question: purpose of LMP ChannelActive message (was
> relationship of RSVP-TE and LMP)
> 
> 
> Didn't see any answers to this question, so I'll try to rephrase and
> make it more focused.
> 
> What is the purpose of the LMP ChannelActive message?
The ChannelActive message is used to indicate that the channel status is
active and should be monitored.

> 
> I'm assuming a call is set up through an optical cross connect (OXC),
> either in response to control plane signalling (e.g. RSVP-TE) or 
> management plane input.
> The OXC has knowledge of which optical links are involved 
> with the call for failure monitoring purposes.
> 
> What additional information would the receipt of a 
> ChannelActive message convey?
This is useful when paths are pre-established (e.g., for path protection).
Although signaling is used to setup the resource reservation, on switchover
you need a mechanism to trigger monitoring of the data channel.

> 
> Regards,
> George.
> edgeflow Inc.
> 329 March Rd., Kanata, ON, Canada, K2K 2E1
> phone: [phone] Ext 287
> fax: [phone]
> 
> 
> >-----Original Message-----
> >From: George Young 
> >Sent: Friday, September 07, 2001 3:47 PM
> >To: [e-mail]
> >Subject: relationship of RSVP-TE and LMP
> >
> >
> >I have two questions about the relationship of RSVP-TE
> >(draft-ietf-mpls-generalized-rsvp-te-03.txt) and LMP
> >(draft-ietf-ccamp-lmp-00.txt).
> >
> >First of all, my understanding of the LMP ChannelActive 
> message is that
> >it is used to indicate to the downstream (relative to data flow
> >direction) node that monitoring should be used.
> >
> >The scenario I have in mind is an RSVP call setup consisting of a
> >bidirectional optical path.  Presumably a switching node has 
> to reserve
> >data channels and associate them with the optical path when an 
> >RSVP PATH
> >message arrives.
> >
> >1) My first question is what is the timing of LMP 
> >ChannelActive messages
> >relative to RSVP messages.
> >
> >Do ChannelActive messages flow downstream (relative to call
> >establishment direction) more-or-less in phase with PATH 
> messages, and
> >upstream (relative to call establishment direction) more-or-less in
> >phase with RESV messages?
> >
> >2) My second question is what addtional information information do
> >ChannelActive messages provide?
> >
> >If a link is to be monitored when associated with an active call, it
> >appears the node already has this information.
> >
> >Regards,
> >George.
> >edgeflow Inc.
> >329 March Rd., Kanata, ON, Canada, K2K 2E1
> >phone: [phone] Ext 287
> >fax: [phone]
> >
> >
> >
>