jiankang, i agree it is interesting. and that is why we have spent the last ten years on extending the internet to space, and running ietf protocols in space. http://personal.ee.surrey.ac.uk/Personal/L.Wood/cleo http://personal.ee.surrey.ac.uk/Personal/L.Wood/dtn Lloyd Wood http://about.me/lloydwood ________________________________________ From: Jiankang Yao [yaojk@xxxxxxxx] Sent: 30 December 2013 09:42 To: Abdussalam Baryun; Wood L Dr (Electronic Eng) Cc: ietf Subject: Re: Re: Chang'E 3 it is a interesting topic. ietf protocols may be extended to space. ________________________________ Jiankang Yao From: Abdussalam Baryun<mailto:abdussalambaryun@xxxxxxxxx> Date: 2013-12-28 06:31 To: l.wood@xxxxxxxxxxxx<mailto:l.wood@xxxxxxxxxxxx> CC: mcr+ietf@xxxxxxxxxxxx<mailto:mcr+ietf@xxxxxxxxxxxx>; ietf@xxxxxxxx<mailto:ietf@xxxxxxxx> Subject: Re: Chang'E 3 I was discussing/commenting on the subject as the thread did about using space internet protocols on satellites, still no standards for space. AB On Friday, December 27, 2013, wrote: AB The Moon is arguably a satellite of Earth, but the distances are different from LEO and GEO. That affects TCP performance. TCP was designed with geostationary satellite hops in mind - see eg RFC829. I use TCP across geostationary satellites daily. I back up my statements with experience and references. What do you back yours with? Why is UDP inefficient? Lloyd Wood http://about.me/lloydwood ________________________________________ From: Abdussalam Baryun [abdussalambaryun@xxxxxxxxx<javascript:;>] Sent: 27 December 2013 06:01 To: Wood L Dr (Electronic Eng) Cc: mcr+ietf@xxxxxxxxxxxx<javascript:;>; ietf@xxxxxxxx<javascript:;> Subject: Re: Chang'E 3 So if TCP has problems then MPTCP has problems then they may not be preferred for that satellite networking. For LEO SATNETs also there are problems for using TCP. The UDP is a good solution in general but not efficient, but always I think the SATNETs may need some special internet transport protocols because they are having more dynamics in the net's lower layers. AB AFAIK vanilla ftp/TCP has (only?) been used on CHIPsat from LEO, but that did not have much data to transfer. We designed http://saratoga.sf.net with the idea of a continuous UDP stream of data from Pluto in mind... Lloyd Wood http://sat-net.com/L.Wood/ ________________________________________ From: ietf [ietf-bounces@xxxxxxxx<javascript:;><javascript:;>] On Behalf Of Abdussalam Baryun [abdussalambaryun@xxxxxxxxx<javascript:;><javascript:;>] Sent: 26 December 2013 16:40 To: Michael Richardson Cc: ietf@xxxxxxxx<javascript:;><javascript:;> Subject: Chang'E 3 Transport protocol for satellites depend on the applications, the network dynamics, links and transmission channels. IMO the use of MPTCP for Back2Earth may not be the best option making the communication complex, not sure why did you hope to use it with this project. AB