[bess] A question about Section 3.3 of RFC 9819
Alexander Vainshtein <Alexander.Vainshtein@rbbn.com> Wed, 10 June 2026 13:16 UTC
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From: Alexander Vainshtein <Alexander.Vainshtein@rbbn.com>
To: Ketan Talaulikar <ketant.ietf@gmail.com>, "skraza@cisco.com" <skraza@cisco.com>, "Jorge Rabadan (Nokia)" <jorge.rabadan=40nokia.com@dmarc.ietf.org>, Wen Lin <wlin@juniper.net>
Thread-Topic: A question about Section 3.3 of RFC 9819
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Date: Wed, 10 Jun 2026 13:15:15 +0000
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Subject: [bess] A question about Section 3.3 of RFC 9819
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Hi all, I have a question about Section 3.3 of RFC 9819<https://datatracker.ietf.org/doc/html/rfc9819#section-3.3>. To the best of my understanding, this section defines the way in which Locator and Function of a SRv6 SID carried in the EVPN IMET route are combined with the Argument of this SID (when applicable) carried in the per-ES Ethernet A-D route if the structures of SIDs described in these routes are not identical as following: * LBL, LNL, and FL of the combined SID are taken from the SID structure carried in the IMET route * AL of the combined SID is taken from the SID structure carried in the per-ES Ethernet A-D route * All the bits in the SID after (LBL+LNL+FN+AL) MUST be set to zeroes. Unless I have missed something, this section does not say how to handle the situation when LBL+LNL+FN+AL) exceeds 128. My guess is this would be yet another case to declare the Argument as unusable. What, if anything, did I miss? Regards, and lots of thanks in advance, Sasha Disclaimer This e-mail together with any attachments may contain information of Ribbon Communications Inc. and its Affiliates that is confidential and/or proprietary for the sole use of the intended recipient. Any review, disclosure, reliance or distribution by others or forwarding without express permission is strictly prohibited. If you are not the intended recipient, please notify the sender immediately and then delete all copies, including any attachments.
- [bess] A question about Section 3.3 of RFC 9819 Alexander Vainshtein
- [bess] Re: A question about Section 3.3 of RFC 98… Ketan Talaulikar
- [bess] Re: [EXTERNAL] Re: A question about Sectio… Alexander Vainshtein