Re: [LOOPS] BOF co-chairs thinking on LOOPS next steps

Carsten Bormann <cabo@tzi.org> Wed, 31 July 2019 23:11 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Date: Thu, 01 Aug 2019 01:11:33 +0200
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To: Michael Welzl <michawe@ifi.uio.no>
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Subject: Re: [LOOPS] BOF co-chairs thinking on LOOPS next steps
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On Aug 1, 2019, at 00:18, Michael Welzl <michawe@ifi.uio.no> wrote:
> 
> if the packet loss ratio is known

Conversely, retransmission can be better to handle random, bursty losses.
(For a definition of “better”, which may depend on your needs.)

But more importantly, for retransmission, the ingress node needs to store copies of packets for a while (and retransmit from this cache), and the egress node needs to send ACKs.  This is much less work per packet than doing FEC, which needs processing of the contents of each packet.  So nodes may be able to do retransmission LOOPS at a higher rate than they would be able to do FEC LOOPS.

Grüße, Carsten