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Re: [core] draft-amsuess-core-repeat-request-tag

Carsten Bormann <cabo@tzi.org> Tue, 18 July 2017 07:52 UTC

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From: Carsten Bormann <cabo@tzi.org>
In-Reply-To: <D58A2C78.83787%goran.selander@ericsson.com>
Date: Tue, 18 Jul 2017 09:52:46 +0200
Cc: Jim Schaad <ietf@augustcellars.com>, "draft-amsuess-core-repeat-request-tag@ietf.org" <draft-amsuess-core-repeat-request-tag@ietf.org>, "core@ietf.org" <core@ietf.org>
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To: Göran Selander <goran.selander@ericsson.com>
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Subject: Re: [core] draft-amsuess-core-repeat-request-tag
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I agree that the name “Repeat” is both confusing and non-descriptive — this option is not about repeating anything.
Freshness Token is more like it.

2.2: What is an "empty CoAP request”?
(A CoAP message can be empty or can carry a request, but cannot be both.)

I’m not sure that the requirement for a 64-bit or larger value is justified; it is the application that defines its freshness requirements, and if the freshness requirement is just about avoiding unnecessary work, a smaller freshness token may be just fine.

There might be other ways to derive/convey a freshness token; maybe it’s worth thinking about how this option would interact with that.

Grüße, Carsten

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