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[Lsr] Regarding SRv6 SID Structure Sub-Sub-TLV in draft-ietf-lsr-isis-srv6-extensions

"Chengli (Cheng Li)" <c.l@huawei.com> Mon, 22 June 2020 11:51 UTC

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From: "Chengli (Cheng Li)" <c.l@huawei.com>
To: "draft-ietf-lsr-isis-srv6-extensions@ietf.org" <draft-ietf-lsr-isis-srv6-extensions@ietf.org>
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Thread-Topic: Regarding SRv6 SID Structure Sub-Sub-TLV in draft-ietf-lsr-isis-srv6-extensions
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Date: Mon, 22 Jun 2020 11:50:59 +0000
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Subject: [Lsr] Regarding SRv6 SID Structure Sub-Sub-TLV in draft-ietf-lsr-isis-srv6-extensions
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Hi authors,

When I read the document, I noticed that the format of the SRv6 SID Structure Sub-Sub-TLV has no reserved bits, which may bring troubles for future extensions.

What if new architecture of SID is proposed? We have to introduce a new SID structure TLV. But actually a backward-compatible format design of this TLV can solve this kind of problems.

IMHO, if we introduced 16 bits reserved bits after the Length, then the length aligns with  64 bits and the future SID structure can be supported.


[cid:image002.jpg@01D648CD.39194020]

Thanks,
Cheng

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