Hi Acee, I do agree that we should explicitly document this in the draft & work on better names for the sub-TLVs that might be confused. I also agree that we need to give the decision explicit consideration; to give this the exposure necessary and consideration for applications was why we had this draft discussed in rtgwg as well as ospf.
In addition to the obvious uses for RSVP-TE, another potential application is the idea of a path-weighted ECMP, where traffic is split to the different next-hops based upon the total path bandwidths out those next-hops. This is a pure IP application (LDP follows of course) and I'd prefer not to lose track of those options when considering the RSVP-TE applications. Alia On Tue, Jun 21, 2011 at 9:06 PM, Acee Lindem <[email protected]> wrote: > Hi Alia, > I guess I agree with Lou - heretofore, we've done TE requirements in the > MPLS/CCAMP WGs and the TE encodings in the IGP WGs. I think we should give > the decision explicit consideration before we branch off and do TE for > application X independently. Additionally, if we do decide to split this off > independently, an E-mail to the list saying there is no overlap is not > sufficient to move forward. At a minimum, I believe we need to: > > 1. Explicitly document this alternate applicability and relationship to > existing TE in the draft. > 2. Determine whether any sub-TLVs can be shared (my opinion was consistent > with yours that there are not due to differences in requirements and > measurement). > 3. Assure the sub-TLVs are appropriately named to avoid confusion between > the latency applications. > > Thanks, > Acee > On Jun 21, 2011, at 2:08 PM, Alia Atlas wrote: > >> Hi Acee, >> >> John Drake and I did take a look at the draft mentioned in CCAMP. It >> had a large number of requirements and extensions to >> a number of different protocols. There is one sub-TLV (latency) that >> appears the same - but the expectations >> as to averaging vs. instantaneous were different. >> >> The OSPF TE Express Path work is fairly self-contained and doesn't >> specify in exact detail how the information >> for the sub-TLVs is measured or obtained. I think it could be used >> for multiple purposes. >> >> Alia >> >> On Tue, Jun 21, 2011 at 12:49 PM, Acee Lindem <[email protected]> >> wrote: >>> Hi Spencer (CCAMP copied as well), >>> >>> Here is a link for everyone's convenience: >>> >>> http://www.ietf.org/id/draft-giacalone-ospf-te-express-path-01.txt >>> >>> At IETF 80, there were questions about overlap with other CCAMP drafts >>> containing interface delay metrics and proposals for new TE sub-TLVs. Have >>> you or your co-authors, done looked at how your draft is positioned versus >>> these other drafts? While these applications have differing goals, the >>> CCAMP/OSPF chairs requested that this analysis be done. >>> >>> http://www.ietf.org/id/draft-wang-ccamp-latency-te-metric-03.txt >>> >>> We would like to avoid having exactly the same information advertised in >>> two different link Sub-TLVs. I'd hope we could agree on common units. >>> >>> Thanks, >>> Acee >>> >>> On Jun 20, 2011, at 4:30 PM, Spencer Giacalone wrote: >>> >>>> Hello everyone, >>>> >>>> As you may have noticed, another version of the OSPF TE Express Path >>>> draft has been posted. We made a number of changes based on feedback >>>> from IETF 80. We invite your comments and suggestions. The main >>>> changes include: >>>> >>>> -We have consolidated some sub-TLVs for efficiency. There are no >>>> longer nominal and anomalous sub-TLVs for delay and loss. The >>>> functionality for signaling steady state verses abnormal performance >>>> for these parameters have been moved into two sub-TLVs (where we used >>>> to have four). >>>> >>>> -In order to advertise both normal and abnormal network performance >>>> state in consolidated sub-TLVs, a bit, called the anomalous (A) but >>>> has been added to certain sub-TLVs. The A bit is set when the measured >>>> value of a parameter exceeds a configured maximum threshold. The A bit >>>> is cleared when the measured value falls below its configured reuse >>>> threshold. If the A bit is clear, the sub-TLV represents steady state >>>> link performance. >>>> >>>> -We changed the encodings of certain variables from floating point to >>>> fixed point. This change permits the addition of the A bit (when >>>> necessary), it allows bit-space reservations to be made, and it >>>> permits a common TLV format across the bulk of the TLVs in the draft. >>>> In addition, the new encodings address concerns about granularity and >>>> interoperability. >>>> >>>> -We added sub-TLVs for Residual Bandwidth and Available Bandwidth. >>>> Residual bandwidth is defined as the Maximum Bandwidth [RFC3630] minus >>>> the bandwidth currently allocated to RSVP-TE LSPs. Available bandwidth >>>> is defined to be residual bandwidth minus the measured bandwidth used >>>> for the actual forwarding of non-RSVP-TE LSP packets. >>>> >>>> -Various other modifications were made across the draft. These >>>> include, but are not limited to, the abstract, the introduction, the >>>> thresholding specifications, and a number of field descriptions. >>>> >>>> -Last, but certainly not least, Stefano Providi has joined the draft >>>> >>>> We look forward to hearing your comments and concerns. >>>> >>>> Thanks, >>>> >>>> Spencer, Alia, Dave, John, Stefano >>>> _______________________________________________ >>>> OSPF mailing list >>>> [email protected] >>>> https://www.ietf.org/mailman/listinfo/ospf >>> >>> _______________________________________________ >>> OSPF mailing list >>> [email protected] >>> https://www.ietf.org/mailman/listinfo/ospf >>> > > _______________________________________________ OSPF mailing list [email protected] https://www.ietf.org/mailman/listinfo/ospf
