- From: James P. Salsman <bovik@best.com>
- Date: Mon, 18 Sep 2000 20:08:26 -0700 (PDT)
- To: pilc@grc.nasa.gov, Reiner.Ludwig@Ericsson.com
- Cc: discuss@apps.ietf.org, ietf-mmms@imc.org, ietf@ietf.org
Reiner,
Thanks for your reply:
>>... There seems to be a lack of understanding about the
>> parameters involved, and most if not all of the important ones are
>> at least touched on in the DoCoMo I-D and the documents it cites.
>
> You need to be more precise. Which parameters are you talking about?
These from http://search.ietf.org/internet-drafts/draft-inamura-docomo-00.txt
Feature Parameter/Recommendation RFC/Status
-------------------------------------------------------------------
MTU size 1500B N/A
Window size 64KB RFC 793 Standard
Initial window 2 mss RFC 2581 Proposed Standard
Initial window up to 4380B RFC 2414 Experimental
Use of SACK Recommend RFC 2018 Proposed Standard
So, given the ECN-like properties of Radio Link Control -- 3G TS 25.322;
which also seems to be incorporated in current versions of GSM --
http://webapp.etsi.org/action/OP/OP20000929/en_301349v080400o.pdf
-- is there really any need to add explicit link condition adaptation
at the TCP or ICMP protocol levels? I don't want to be in a position
of advocating the change or addition of anything to those protocols
unless absolutely necessary.
As far as robust wireless TCP goes, you are absolutely right that good
service requires a maximum RTO shorter than the standard 64 seconds.
What is that value in your TCP-Eiffel?
And one parameter that the DoCoMo draft doesn't mention (perhaps it
goes without saying to most people) is a total retransmit timeout much
longer than the typical 2-9 minutes. Again, what do you use; an hour?
Cheers,
James
P.S. Please keep at least ietf-mmms@imc.org in on this, as the lack
of ubiquitous wireless TCP is related to Mobile Multimedia Messaging
applications.
Received on Monday, 18 September 2000 23:10:00 UTC