Subject: [ledbat] open issues, applicability statement

From: "Rolf Winter" <[email-masked]>
Date: Tue, 8 Jun 2010 16:07:59 +0200

Hi,

third open issue:

3. Applicability
I myself had a few comments on clarifications in the document during the last meeting. There maybe are a few applicability statements we could add to the draft. E.g. today there are still a lot of rural areas served by DSL with really low uplink capacities. LEDBAT will not be able to achieve the delay target here if full-sized segments are sent. A single segment will violate the 25 ms. This could be added, with a comment that adaptive segment sizing is not in scope of the document but is not precluded by the document either. 
Another hint could be given to home gateway manufactures which like to classify P2P traffic into low priority class queues. Which is fine when they run over TCP, but LEDBAT deals with the "problem" already so there is no need to put it into a different queue. In fact we did some measurements that show that in certain circumstances LEDBAT will not fulfil its design goals in such a low priority queue anymore. But that is home gateway implementation-specific. There were arguments against this. Please discuss.

Best,

	Rolf

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