Re: [Teas] Adam Roach's No Objection on draft-ietf-teas-assoc-corouted-bidir-frr-06: (with COMMENT)

Adam Roach <adam@nostrum.com> Fri, 26 October 2018 19:29 UTC

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To: "Rakesh Gandhi (rgandhi)" <rgandhi@cisco.com>, The IESG <iesg@ietf.org>
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From: Adam Roach <adam@nostrum.com>
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Date: Fri, 26 Oct 2018 14:28:53 -0500
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Subject: Re: [Teas] Adam Roach's No Objection on draft-ietf-teas-assoc-corouted-bidir-frr-06: (with COMMENT)
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On 10/26/18 12:35 PM, Rakesh Gandhi (rgandhi) wrote:
>      Appendix A:
>      
>      >     0                   1                   2                   3
>      >     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
>      >    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>      >    |                    IPv4 LSP Source Address                    |
>      >    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>      >    |           Reserved            |            LSP-ID             |
>      >    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>      
>      What are implementors expected to set the "Reserved" bytes to?
>      
> <RG> Added: “The Reserved flags MUST be set to 0 on transmission and ignored when received.”


Are you sure that's right? If so, it's not clear how the recipient knows 
whether the Extended Association ID is in this format (as its use is a 
"may"), and whether it's safe to ignore them.  I would expect this to 
simply say that the Reserved bits are set to 0 on transmission without 
saying anything about reception. This isn't as much for the sake of the 
protocol (since the value doesn't really matter) as it is to help 
implementors out.

/a