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RE: Layer 2 Switching Caps LSPs



Dimitri,

Can the off-line discussion be summarized for the benefit of those on
the list who did not participate?  For me, the draft (and the current
discussion on the list) have not clearly articulated the problem being
addressed.  If a summary of the conclusions of the off-line discussion
will do this, it would be useful.

I am also interested to know what is lacking in the current GMPLS RFCs
with respect to ATM and Frame Relay support that necessitates including
them in this new draft (presumably this is a part of the problem to be
solved).

Regards,
Ben

> -----Original Message-----
> From: owner-ccamp@ops.ietf.org [mailto:owner-ccamp@ops.ietf.org] On
Behalf
> Of dimitri papadimitriou
> Sent: Thursday, January 27, 2005 6:35 PM
> To: David Allan
> Cc: 'Adrian Farrel'; 'Shahram Davari'; ccamp@ops.ietf.org
> Subject: Re: Layer 2 Switching Caps LSPs
> 
> dave - there was a lengthy off-line discussion suggested by the chairs
> intended to explain you the scope of the draft and its relatioship
with
> the ethernet data plane (after the question you raised during the f2f
> meeting) - this has been done and we have explained (via a lengthy
> exchange of e-mails) that this document and so the use of gmpls to
> control ethernet frame flows, is not targeting control of bridged
> ethernet environments - if this is not clear from the current document
> introduction we would have also to work on this part of the document -
> therefore, the below reference to MSTP is not in the current scope; on
> the other side, the use of the term "VLAN label" has created some
> confusion; therefore, in a next release i will simply refer to a
"label"
> of 32 bits (unstructured) because the intention was (and still is) to
> find an easy way to map the control of the ethernet frame flows on
each
> device they traverses without making any assumption on how this flow
is
> processed inside each node at the data plane level (note: on label
> values, RFC 3946 took an equivalent approach - for circuits - where
> sonet/sdh multiplexing structures have been used to create unique
> multiplex entry names i.e. labels - this concept is here applied for
> "virtual" circuits), so, if the working group is willing to enter into
a
> data plane oriented discussion to clarify the behaviour(s) onto which
> the present approach would be potentially applicable this is fine with
> me as long as we are within the scope of the initial motivations
> 
> thanks,
> - dimitri.
> 
> David Allan wrote:
> > Hi Adrian:
> >
> > Your suggestion is in a way reasonable but with the caveat that in
IEEE
> > terms, a bridging topology is currently all VLANs (802.1Q single
> spanning
> > tree) or partitioned into specific ranges (I believe 64 in 802.1s
> although I
> > do not claim to be an expert).
> >
> > If the PEs were to implement a bridge function and we were using
GMPLS
> to
> > interconnect them, then the control plane should be identifying
either
> all
> > VLANs (single spanning tree, which I beleive the draft covers by
> referring
> > simply to Ethernet port) or a VLAN range to be associated with the
LSP
> > consistent with 802.1s if it is to operate to interconnect bridges
> defined
> > by the IEEE...
> >
> > I suspect assuming any other behavior (e.g. LSP for single VLAN tag)
> would
> > go outside the boundary of what is currently defined...so alignment
with
> > 802.1s IMO would be a minimum requirement if we are to consider
carrying
> > VLAN information in GMPLS signalling....
> >
> > cheers
> > Dave
> >
> > You wrote....
> >
> >>Hi,
> >>
> >>The authors of the draft might like to clarify for the list
> >>exactly what data plane operations they are suggesting. To me
> >>it seems possible that the draft is proposing VLAN ID
> >>*swapping*. But an alternative is that the VLAN ID is used as
> >>a label, but that the same label is used for the full length
> >>of the LSP.
> >>
> >>Adrian
> >
> >
> >
> > .
> >
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