Re: [core] Large asynchronous notifications under DDoS: New BLOCK Option?

Christian Amsüss <christian@amsuess.com> Wed, 08 April 2020 09:06 UTC

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Date: Wed, 8 Apr 2020 11:04:36 +0200
From: Christian =?iso-8859-1?Q?Ams=FCss?= <christian@amsuess.com>
To: mohamed.boucadair@orange.com
Cc: "core@ietf.org" <core@ietf.org>, "Jon Shallow (supjps-ietf@jpshallow.com)" <supjps-ietf@jpshallow.com>, "dots@ietf.org" <dots@ietf.org>
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Subject: Re: [core] Large asynchronous notifications under DDoS: New BLOCK Option?
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Hello Med,

On Tue, Apr 07, 2020 at 03:51:14PM +0000, mohamed.boucadair@orange.com wrote:
> I don't see where in the two drafts an observer can request a particular missing fragment. 

Observation combined with block-wise transfer generally has the observer
request all the remaining blocks when an updates comes in, as
illustrated in [1]. Those do not even necessarily need to be requested
in sequence.

If a mechanism gets added that allows the server to send additional
blocks after a first request (and I'd appreciate that, maybe we can get
that resurfaced in the upcoming meeting's AOB section), the client may
miss some of them, but can still fall back to that original mechanism.

Kind regards
Christian

[1]: https://tools.ietf.org/html/rfc7959#section-3.4

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