Erik,
Have you got a chance to look at revision 16 and check if it addresses your
DISCUSS?

Thanks,
Rishabh.

On Wed, Oct 29, 2025 at 7:57 AM Rishabh Parekh <[email protected]> wrote:

> Erik,
> The new revision of the draft has the above change in the text. Can you
> please take a look and confirm if this addresses your DISCUSS?
>
> Thanks,
> Rishabh.
>
> On Sun, Oct 19, 2025 at 9:42 AM Rishabh Parekh <[email protected]> wrote:
>
>> Erik,
>> This is an optional MAY behavior because an egress PE must be able to
>> identify the ingress PE that sent the IPv6 encapsulated packet in order to
>> determine the MVPN context from upstream assigned SID. This may not be
>> feasible from examining the IPv6 source address of the packet, unless the
>> egress PE knows what IPv6 address ingress PEs would use for encapsulation.
>> So, on second thought, it is better to drop this text from the draft and
>> just mandate that an egress PE must not forward the packet based on the
>> End.DTMC4/6 SID in the SRH.
>>
>> Rishabh.
>>
>> On Sat, Oct 18, 2025 at 6:05 PM Erik Kline <[email protected]> wrote:
>>
>>> Thank you.
>>>
>>> Might another option be something in the RFC 9602 space?  Or a new space
>>> from 5f00::/8 (minus the 9602 prefix)?
>>>
>>> On Sat, Oct 18, 2025 at 5:19 PM Rishabh Parekh <[email protected]>
>>> wrote:
>>>
>>>> Erik,
>>>> Yes, the discard prefix 0100:64 from RFC 6666 can be used. My only
>>>> concerns are in practice Locator prefixes are assigned from /32 or /48
>>>> prefix blocks, and I know some implementations may assume these prefix
>>>> blocks for the LOC portion of SRv6 SIDs. The /64 discard prefix LOC will
>>>> push the FUNCT further in SRv6 SID.
>>>>
>>>> That said, I can certainly add it as an option in addition to ULA.
>>>>
>>>> Rishabh.
>>>>
>>>> On Sat, Oct 18, 2025 at 3:28 PM Erik Kline <[email protected]> wrote:
>>>>
>>>>> This helps, thank you.
>>>>>
>>>>> A ULA is not necessarily non-routable, though.  Would it be possible
>>>>> to use the RFC 6666 discard prefix?
>>>>>
>>>>> On Thu, Oct 16, 2025 at 9:48 PM Rishabh Parekh <[email protected]>
>>>>> wrote:
>>>>>
>>>>>> Erik,
>>>>>>
>>>>>> Reply inline @ [RP]
>>>>>>
>>>>>> On Thu, Oct 16, 2025 at 8:55 PM Erik Kline via Datatracker <
>>>>>> [email protected]> wrote:
>>>>>>
>>>>>>> Erik Kline has entered the following ballot position for
>>>>>>> draft-ietf-bess-mvpn-evpn-sr-p2mp-15: Discuss
>>>>>>>
>>>>>>> When responding, please keep the subject line intact and reply to all
>>>>>>> email addresses included in the To and CC lines. (Feel free to cut
>>>>>>> this
>>>>>>> introductory paragraph, however.)
>>>>>>>
>>>>>>>
>>>>>>> Please refer to
>>>>>>> https://www.ietf.org/about/groups/iesg/statements/handling-ballot-positions/
>>>>>>> for more information about how to handle DISCUSS and COMMENT
>>>>>>> positions.
>>>>>>>
>>>>>>>
>>>>>>> The document, along with other ballot positions, can be found here:
>>>>>>> https://datatracker.ietf.org/doc/draft-ietf-bess-mvpn-evpn-sr-p2mp/
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> ----------------------------------------------------------------------
>>>>>>> DISCUSS:
>>>>>>>
>>>>>>> ----------------------------------------------------------------------
>>>>>>>
>>>>>>> # Internet AD comments for draft-ietf-bess-mvpn-evpn-sr-p2mp-15
>>>>>>> CC @ekline
>>>>>>>
>>>>>>> * comment syntax:
>>>>>>>   - https://github.com/mnot/ietf-comments/blob/main/format.md
>>>>>>>
>>>>>>> * "Handling Ballot Positions":
>>>>>>>   -
>>>>>>> https://ietf.org/about/groups/iesg/statements/handling-ballot-positions/
>>>>>>>
>>>>>>> ## Discuss
>>>>>>>
>>>>>>> ### S3.1.2
>>>>>>>
>>>>>>> * "The advertising ingress PE MAY
>>>>>>>    use a non-routable prefix as LOC of the SRv6 Multicast Service
>>>>>>> SID to
>>>>>>>    prevent packets being routed to it based on the SID."
>>>>>>>
>>>>>>>   Can you clarify what is intended here?  I'm afraid I couldn't
>>>>>>> figure out
>>>>>>>   what is meant by a non-routable prefix to prevent packets being
>>>>>>> routed
>>>>>>>   to the advertising router.
>>>>>>>
>>>>>>>   Possibly I just don't have the right mental model yet.  Is this
>>>>>>> for some
>>>>>>>   scenario where discarding traffic is desired?
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>> [RP] The use-case is when an SRv6 P2MP tree is shared across two or
>>>>>> more MVPN contexts. In this case, the ingress PE advertises an
>>>>>> upstream-assigned SID (one of End.DTMC4/6 specified in Section 5.21) to
>>>>>> identify specific MVPN context for payload processing at an egress PE
>>>>>> (which receives MVPN customer payload on the shared SRv6 P2MP tree). This
>>>>>> upstream assigned SID is carried in SRH of an IPv6 encapsulated packet 
>>>>>> from
>>>>>> the ingress PE. On the egress PE, this SID (or specifically FUNCT portion
>>>>>> of the SID) should just be used to derive the MVPN context. If an egress 
>>>>>> PE
>>>>>> mistakenly uses this SID to forward the packet (by setting it in the IPv6
>>>>>> DA header), the packet will incorrectly routed back to the ingress PE if
>>>>>> the LOC portion of the SID identifies the ingress PE. To prevent 
>>>>>> incorrect
>>>>>> re-routing using the SID, the ingress PE may use a non-routable IPv6 
>>>>>> prefix
>>>>>> (such as Unique Local Address prefix) as the LOC portion of End.DTMC4/6 
>>>>>> SID.
>>>>>>
>>>>>> I hope this answers your question.
>>>>>>
>>>>>>
>>>>>>>
>>>>>>>
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>>>>>>>
>>>>>>
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