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Re: [6lo] draft-ietf-6lo-minimal-fragment-00: When to remove VRB entries?

Yasuyuki Tanaka <yasuyuki.tanaka@inria.fr> Thu, 07 February 2019 10:58 UTC

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To: Martine Lenders <m.lenders@fu-berlin.de>
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From: Yasuyuki Tanaka <yasuyuki.tanaka@inria.fr>
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Subject: Re: [6lo] draft-ietf-6lo-minimal-fragment-00: When to remove VRB entries?
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Hi Martine,

On 2/6/2019 3:49 PM, Martine Lenders wrote:
> For the success case I could of course just count the bytes of the 
> fragments and remove the VRB entry once I reach the datagram size, 
> however this does not account for possibly received duplicates (unless I 
> keep track of at least the intervals of all received fragments which of 
> course costs more memory).

If you receive a fragment having a fragment_tag which you've already 
seen and the fragment_tag is not associated with any entry in the VRB 
table, you can consider it as a duplicate or late-arriving fragment. 
Then, you can drop the received fragment safely.

Best,
Yatch

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