Re: [Ntp] draft-mlichvar-ntp-ntpv5-01

g16 <g16g16g16@gmail.com> Thu, 10 December 2020 16:23 UTC

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Date: Fri, 11 Dec 2020 01:23:07 +0900
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To: Miroslav Lichvar <mlichvar@redhat.com>, ntp@ietf.org
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Subject: Re: [Ntp] draft-mlichvar-ntp-ntpv5-01
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Hi Miroslav

Thank you for your draft 01 work.

"8.  NTPv5 Negotiation in NTPv4" helped me understand.

May I ask you a question?

As written, Some NTPv4 implementations drop requests with unknown
extensions. As I read the draft, there is no mention of handling unknown
extensions. So,  can NTPv5 make it a MUST requirement to just ignore
unknown extensions instead of dropping packets? (Counted for symmetry of
data volume)

I'd say it's good for future extensibility.

When new extensions are defined in the future, a client indicates a
supported extension by sending the extension in a request, and the server
can only send extensions that the client supports.The  client knows if the
server understands the extension by seeing the same extension in the
response.

Thank you for reading.

Regards,

yuki