[Iccrg] A Wireless Channel Model Based Rate Control (WMRC) Scheme (WAS Re: present a draft)

[Lachlan Andrew]

Greetings all,

Although I'm a theorist at heart, on a cursory glance I also feel that
this may be too theoretical for an IETF standard.  There are many
possible channel models (for many possible channels), and
standardizing transmission based on one should be done with caution.

IETF documents are mainly useful for issues that need agreement to be
implemented.  The main reason congestion control algorithms (as
distinct from protocols) need agreement is for "fairness".  Fairness
in systems with different channels is a very complicated issue, which
doesn't seem to be addressed in this draft.

$0.02,
Lachlan

2010/10/27 Ingemar Johansson S <ingemar.s.johansson at ericsson.com>:
> Hi
>
> I have briefly read through this draft. To me it seems to be quite teorethical and rely on the assumption that wireless access generally suffers from packet loss.
> My opinion is that with 3GPP access, at least for OTT (over the top) transmission, non-congestion related loss is relatively rare. One can for instance refer to 3GPP TS 23.203 http://www.3gpp.org/ftp/Specs/archive/23_series/23.203/23203-a10.zip table 6.1.7 (page 32).
> Best effort traffic is typically meant to be transported over a QCI=9 bearer. The packet loss rate is targeted at 10^-6. These bearers can drop packet as a result of congestion but as said before non-congestion related losses are expected to be rare.
>
> I have no opinion regarding other wireless access types however.
>
> Have you been able to test this algorithm in a real system ?, one possible problem I see is that one build a model of a system based on past data, as users move around this model may only be fairly correct as long as the user stays in one cell. As soon as the user makes a handover to another cell the model may change completely.
>
> /Ingemar
>
>
>> Message: 1
>> Date: Mon, 25 Oct 2010 21:05:47 +0200
>> From: Michael Welzl <michawe at ifi.uio.no>
>> Subject: Re: [Iccrg] present a draft
>> To: "iccrg at cs.ucl.ac.uk list" <iccrg at cs.ucl.ac.uk>
>> Message-ID: <9F93C80F-FD89-4645-9355-432B17684622 at ifi.uio.no>
>> Content-Type: text/plain; charset=UTF-8; format=flowed; delsp=yes
>>
>> ...so what's the group's opinion on this proposal?



-- 
Lachlan Andrew  Centre for Advanced Internet Architectures (CAIA)
Swinburne University of Technology, Melbourne, Australia
<http://caia.swin.edu.au/cv/landrew>
Ph +61 3 9214 4837