Hi, Peter: I think the logic is the following: FAPM is the sub-TLV of TLV 135,235,236 and 237, then it extends these TLVs for advertising prefixes in algorithm 0 to other Flexible Algorithm. Then I see no reason to define the new top-TLV to encoding the similar information.
Aijun Wang China Telecom > On May 3, 2022, at 19:16, Peter Psenak <[email protected]> > wrote: > > Hi Aijun, > >> On 03/05/2022 11:57, Aijun Wang wrote: >> Hi, Peter： >> Different data planes use different Flex-Algorithm and associated metric, >> they can’t be mixed. >> Or, would you like to point out why the following scenarios can’t be >> achieved via the FAPM? >> 1) The PE router has three loopback addresses(Lo1-Lo3), each associated with >> different Flex-ALgorithhms, and also different metrics. They are advertised >> via the FAPM, no MPLS SIDs are associated with these loopack prefixes >> advertisements. >> 2) The PE router has also another inter-area/inter-domain prefixes(IPextra), >> with the FAPM and MPLS SID advertised via the prefixes advertisements. >> When the PE in other ends want to send the traffic to theses addresses: >> 1) To the formers three destinations(Lo1-Lo3), the FIB that are formed by >> the associated FAPM will be used, that is, the IP-based forwarding will be >> selected. >> 2) To the Inter-area/inter-domain prefixes the FIB that are formed via the >> FAPM and the associated SID, the MPLS-based forwarding will be selected. >> Why can’t they coexist? > > FAPM Sub-TLV is a sub-TLV of TLVs 135, 235, 236, and 237. These TLVs > advertise the reachability of the prefix in algorithm 0. > > For an IP algo prefix, which is associated with the flex-algorithm, the > reachability in algorithm 0 must not be advertised. So we have to use a > different top level TLV. > > > thanks, > Peter > > > >> Aijun Wang >> China Telecom >>>> On May 3, 2022, at 16:05, Peter Psenak >>>> <[email protected]> wrote: >>> >>> Aijun, >>> >>>> On 03/05/2022 09:59, Aijun Wang wrote: >>>> Hi, Peter: >>>> The definition of FAPM for IS-IS and OSPF doesn’t prevent from it is used >>>> for the intra-area prefixes. >>>> If we advertise the different loopback addresses via the FAPM, associate >>>> them to different Flex-Algo and related metrics, and does not allocate the >>>> MPLS SID, we can achieve the IP-Flex effect then. >>> >>> as I said, we can not mix metrics for different data-planes. >>> >>>> So, what’s the additional value of the IP-Flexalgo draft then? >>> >>> please read the draft. It defines the flex-algo for IP data plane. >>> >>> thanks, >>> Peter >>> >>> >>> >>>> Aijun Wang >>>> China Telecom >>>>>> On May 3, 2022, at 14:46, Peter Psenak >>>>>> <[email protected]> wrote: >>>>> >>>>> Aijun, >>>>> >>>>>> On 03/05/2022 00:47, Aijun Wang wrote: >>>>>> Hi, Acee: >>>>>> The questions raised at >>>>>> https://mailarchive.ietf.org/arch/msg/lsr/RlHphXCwxMbgGvcBV_m24xiDzS0/ >>>>>> <https://mailarchive.ietf.org/arch/msg/lsr/RlHphXCwxMbgGvcBV_m24xiDzS0/> >>>>>> has not been answered. >>>>> >>>>> IS-IS Flexible Algorithm Prefix Metric Sub-TLV” and “OSPF Flexible >>>>> Algorithm Prefix Metric Sub-TLV” are defined for advertisement of >>>>> algorithm specific metric for inter-area inter-AS prefixes for SR-MPLS >>>>> data-plane. >>>>> >>>>> SR MPLS and IP are independent data-planes used for flex-algo. We can not >>>>> mix their metric. >>>>> >>>>> thanks, >>>>> Peter >>>>> >>>>>> Aijun Wang >>>>>> China Telecom >>>>>>>> On May 2, 2022, at 23:00, Acee Lindem (acee) >>>>>>>> <[email protected]> wrote: >>>>>>> >>>>>>> The WG last call has completed. We will submit an updated version of >>>>>>> the document for publication with the terminology changes based on the >>>>>>> discussion amongst the authors, Ketan, Robert, Gyan, and others. >>>>>>> >>>>>>> Thanks, >>>>>>> Acee >>>>>>> >>>>>>> *From: *Lsr <[email protected]> on behalf of "Acee Lindem (acee)" >>>>>>> <[email protected]> >>>>>>> *Date: *Thursday, April 7, 2022 at 3:07 PM >>>>>>> *To: *"[email protected]" <[email protected]> >>>>>>> *Cc: *"[email protected]" >>>>>>> <[email protected]> >>>>>>> *Subject: *[Lsr] Working Group Last Call for >>>>>>> draft-ietf-lsr-ip-flexalgo-04 - "IGP Flexible Algorithms >>>>>>> (Flex-Algorithm) In IP Networks" >>>>>>> >>>>>>> This begins a WG last call for draft-ietf-lsr-ip-flexalgo-04. The >>>>>>> draft had a lot of support and discussion initially and has been stable >>>>>>> for some time. Please review and send your comments, support, or >>>>>>> objection to this list before 12 AM UTC on April 22^nd , 2022. >>>>>>> >>>>>>> Thanks, >>>>>>> Acee >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Lsr mailing list >>>>>>> [email protected] >>>>>>> https://www.ietf.org/mailman/listinfo/lsr >>>>> >>> >> _______________________________________________ >> Lsr mailing list >> [email protected] >> https://www.ietf.org/mailman/listinfo/lsr > _______________________________________________ Lsr mailing list [email protected] https://www.ietf.org/mailman/listinfo/lsr
