[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Moving right along ... generalized-signaling-06
On the specific section on the waveband switching, we also agree that
further work is required to achieve a consistent definition of waveband
switching in GMPLS.
, we try to address some of the issues concerning waveband switching,
notably by the introduction of a waveband switch capable interface
(WBSC). We also try to remain as compliant as possible with the current
proposition (GMPLS-SIG) for the proposed enhancements. However, we
encourage that waveband switching issues be restudied before putting it
back on the standard track.
It is clear that an in-depth analysis of the constraints and
requirements for waveband switching could leed to best suited proposals.
What are the next step : take it off GMPLS-SIG for further work (ad hoc
design team?), other ideas ?
Richard Douville et al.
Ben Mack-Crane wrote:
> See comments below.
> Lou Berger wrote:
> > At 01:09 PM 10/29/2001, Ben Mack-Crane wrote:
> > >After reviewing draft-ietf-mpls-generalized-signaling-06.txt I have
> > >a few comments and questions:
> > >
> > >1) There seems to be no difference as far as label allocation
> > > is concerned between LSP Encoding Types Ethernet V2/DIX (2)
> > > and Ethernet 802.3 (10). One Encoding type would seem to
> > > be sufficient.
> > I agree, but some feel that this is needed to properly establish LSPs in
> > systems what would terminate each type differently.
> I don't recall seeing anything on the list about the reasoning about this.
> can someone provide a pointer to where this was described?
> Since LSP Encoding type is intended to describe the LSP for transit nodes
> and G-PID is intended to describe the LSP contents for the purpose of
> terminating it at the ends, information relevant only to termination
> should be conveyed in G-PID.
> Perhaps changing the name of this LSP Encoding Type to "Ethernet Phy"
> would make this clearer.
> > >2) G-PID types (19), (20), and (21) are repeats of (16), (17),
> > > and (18).
> > see latest draft...
> Thanks for fixing this. The new (19) should probably be "VC-11 in TU-12."
> > > Since the Siganl Type will indicate whether the
> > > LSP is VC-11/VT1.5 or VC-12/VT2, this encoding is redundant.
> > the fields serve different purposes.
> > >3) G-PID type (37) Lambda seems insufficient (too vague) to
> > > support interoperability. Is there any practical use for this
> > > value?
> > yes, it's needed when doing fiber/port switching.
> > >4) In the "Bandwidth Encoding" section it states "For non-packet LSPs, it
> > > is useful to define discrete values to identify the bandwidth of the
> > > LSP." For SONET/SDH this is unnecessary given the Signal Type is
> > > provided. For the other non-packet LSP types (Lambda and Fiber)
> > > it is not clear that all the values cited in the example are relevant
> > > (for example, a DS0 lambda would seem wasteful...).
> > > This is confusing, and should be clarified. In fact, a description of
> > > exactly why this field is required is needed.
> > We've gone over this text multiple times. Do you have any suggested wording.
> I would gladly suggest wording if I understood the use for this. It has no use
> for Packet, PDH, SDH/SONET, or "Digital Wrapper," so I assume it is for Lambda
> or Fiber. However, several of the examples are not appropriate for this.
> Perhaps this should be moved to a technology specific document since it is
> not really general anyway.
> > >5) The Waveband ID "is selected by the sender and reused in all
> > > subsequent related messages." This seems more the sort of thing that
> > > should be negotiated by LMP rather than during connection setup.
> > The ID has significance within signaling context of the sender. (like
> > message id). I don't think using another layer of complexity for provate
> > information makes sense.
> > >6) The definition of Start Label and End Label in waveband switching seems
> > > inconsistent with the behavior described in generalized-rsvp-te-05.
> > I don't see this. Feel free to suggest wording.
> Does anyone else see an inconsistency here? I would be interested in hearing
> from someone who understands the waveband content.
> I am concerned that the waveband proposal is speculative and not ready to
> progress toward RFC status. Perhaps the waveband content should be removed
> and the sections marked FFS.
> > >
> > >7) In Protection Information it states "The resources allocated for a
> > > secondary LSP MAY be used by other LSPs until the primary LSP fails
> > > over to the secondary LSP." This may not always be the case. An
> > > explicit flag indicating whether or not extra traffic may use the
> > > secondary path resources is needed.
> > ??? This is the purpose of this bit.
> This is not clear from the definition. The bit is defined as indicating
> the LSP is a secondary (or protecting) LSP and in 1+1 protection the
> secondary LSP may not be used for extra traffic.
> Perhaps the problem here is that protection features are being defined
> before the protection framework and requirements are done. Is this
> presupposing some particular outcome of the recovery work in CAMP?
> > >8) The Administrative Status Information includes a bit indicating
> > > "Administratively down," but there is no reference to a definition
> > > of this state. Is this intended to mirror the MIB variable? If so,
> > > a reference is needed. If not, more definition is needed to ensure
> > > the local behaviors driven by this bit are in some way consistent.
> > > Whether this state defintion is consistent with current transport
> > > network operations should also be considered.
> > Per the document:
> > The actions taken by a node based on a state local decision.
> > >9) In Interface Identification, the IP Address for types 3,4, and 5 is
> > > described as possibly "an IP address associated with the router ID."
> > > Is this intended to mean the Router ID or any IP address owned by
> > > the node? It seems the Router ID is the simplest solution, but the
> > > wording is not clear.
> > Text has been reworded in 07. It's any IP address configured on a node.
> > >10)In describing the Interface ID the statement "The special value
> > > 0xFFFFFFFF can be used to indicate the same label is to be valid
> > > across all component links." What is the "label" referred to in
> > > this case?
> > I'll reword in the post IETF last call rev of the document.
> > Lou
> > >Regards,
> > >Ben Mack-Crane
Richard Douville Richard.Douville@alcatel.fr
Alcatel Research & Innovation Photonic Networks Unit, URP
Route de Nozay Tel: 33-1-18.104.22.168
F-91460 Marcoussis, France. Fax: 33-1-22.214.171.124