Michael, That first sentence quoted below has the key -- Basically, the S-BFD discriminator is tied to the node. It is an RI piece, with very a very small amount of data. Further, it is information that relates directly to OSPF, as IGPs are clients and users of S-BFD. It is not OSPF data per se, you are correct, but it is a "information relating to the aggregate OSPF router".
Thanks, Carlos. On Sep 26, 2014, at 9:08 AM, Karsten Thomann <karsten_thom...@linfre.de> wrote: > Hi, > > RFC 4970 Section 3 includes: > > The purpose of the Router Information (RI) LSA is to advertise > information relating to the aggregate OSPF router. Normally, this > should be confined to TLVs with a single value or very few values. > It is not meant to be a generic container to carry any and all > information. > > I think the first sentence allows it, as it is related to the ospf router, > even if it is not an ospf internal information. > Michael is right that not everything should be in the RI LSA as already > mentioned in the RFC, increasing the count of LSAs which need to be > flooded across the domain has also drawbacks in term of scalability. > > Regards, > > Karsten > > > Am 26.09.2014 08:58, schrieb Manav Bhatia: >> Hi Michael, >> >> :-) >> >> Lets not deal with analogies (my bad!) lest we get misled by those. >> >> Clearly you and I look at RI LSAs differently. I dont think what youre >> suggesting is even remotely preposterous. However, i do believe that >> RIs can serve more than merely announcing OSPF specific router >> capabilities. >> >> And once again, we already have a precedent where RI was used for >> announcing non OSPF specific capability -- which means that the >> co-authors of this draft arent the only ones who think of RIs as being >> a generic tool for router capability advertisement. >> >> Lets hear what others have to say on this. >> >> Cheers, Manav >> >> >> On Fri, Sep 26, 2014 at 11:53 AM, Michael Barnes <mjbar...@cisco.com> wrote: >>> Hi Manav, >>> >>> That's a pretty funny analogy. I've got another one for you. >>> >>> Say the RI LSA is like a corporate learjet for a tool company. When it gets >>> flown around it's never full so you decide to use it to ship wrenches on it >>> along with the executives. You're proud of your wrenches and want everyone >>> to know how great they are, but do you really want to ship them that way? >>> Maybe it's better to put the wrenches in their own vehicle. >>> >>> So to be a little more serious, if the router wants to proudly proclaim its >>> S-BFD capability then it deserves its own special LSA rather than being >>> packed into one used for other things. >>> >>> Cheers, >>> Michael >>> >>> >>> On 09/25/2014 06:27 PM, Manav Bhatia wrote: >>>> Hi Michael, >>>> >>>> Very interesting. >>>> >>>> I think there is a disconnect because of our interpretation of what an >>>> RI LSA is envisioned to carry. I assume its meant to advertise >>>> "optional router capabilities" while you believe its to be used solely >>>> for advertising "optional OSPF router capabilities". IMO, limiting the >>>> scope of RI to just OSPF is like using a humvee with all its bells and >>>> whistles to distribute balloons to the children in your friendly >>>> neighborhood park! We wanted a mechanism wherein each router could >>>> proudly tell the world that it was an S-BFD capable node and along >>>> with it also advertise the unique discriminator that the others would >>>> use to reach it. RI we felt, was the perfect tool that we could use >>>> for this purpose. >>>> >>>> And btw we're not the first ones to use RI for advertising a router >>>> capability that isnt pertinent to OSPF per se (RFC 5088). >>>> >>>> Cheers, Manav >>>> >>>> On Fri, Sep 26, 2014 at 12:47 AM, Michael Barnes <mjbar...@cisco.com> >>>> wrote: >>>>> Hi Manav, >>>>> >>>>> Perhaps I missed some earlier discussion, on why you decided to add the >>>>> S-BFD Discriminator TLV to the RI LSA, but I would prefer it not be in >>>>> that >>>>> LSA. I would like to leave the RI LSA with only information pertinent to >>>>> OSPF rather than pollute it with information for which OSPF has no >>>>> interest. >>>>> If you're concerned with a trend of creating a new Opaque type for every >>>>> application which might want OSPF to carry information for it, then I >>>>> would >>>>> suggest we create a generic Application Information LSA. >>>>> >>>>> Regards, >>>>> Michael >>>>> >>>>> >>>>> On 05/30/2014 01:47 AM, Manav Bhatia wrote: >>>>>> >>>>>> Hi, >>>>>> >>>>>> We had submitted the following draft a couple of weeks ago. >>>>>> >>>>>> http://tools.ietf.org/id/draft-bhatia-ospf-sbfd-discriminator-00.txt >>>>>> >>>>>> This draft introduces a new OSPF RI TLV that allows OSPF routers to >>>>>> flood the S-BFD discriminator values in the routing domain. >>>>>> >>>>>> S-BFD is a new charter item (will be approved very soon) in the BFD WG. >>>>>> >>>>>> Would appreciate comments on this. >>>>>> >>>>>> Cheers, Manav >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> OSPF mailing list >>>>>> OSPF@ietf.org >>>>>> https://www.ietf.org/mailman/listinfo/ospf >>>>>> >>>> . >>>> >> _______________________________________________ >> OSPF mailing list >> OSPF@ietf.org >> https://www.ietf.org/mailman/listinfo/ospf > > _______________________________________________ > OSPF mailing list > OSPF@ietf.org > https://www.ietf.org/mailman/listinfo/ospf _______________________________________________ OSPF mailing list OSPF@ietf.org https://www.ietf.org/mailman/listinfo/ospf
