On Fri, Mar 19, 2010 at 4:25 PM, Harti Brandt <firstname.lastname@example.org> wrote:
> On Fri, 19 Mar 2010, Atis wrote:
> A>2) SCPS, Space Communication Protocol Standards
> A>This is probably my first project choice if all goes well. Space
> A>protocols - this sounds very cool :) and is related to my research
> A>interests (IP protocols over lossy networks). The first question is -
> A>do these protocols also have some practical value? This is not-so-new
> A>family of protocols, but it seems that very few implementations exist.
> A>On the one hand, this could be a good thing, because now there a
> A>chance for FreeBSD to be the first OS with open source SCPS
> A>implementation. On the other hand - lack of use seems to imply lack of
> A>importance and usefulness. The second question - is complete
> A>implementation of all the protocols supposed? At first glance it seem
> A>that e.g. SCPS Security Protocol simply duplicates the functionality
> A>already present in IPSec. Still, support for all protocols may be
> A>needed for interoperability and completeness of the implementation.
> A>Also, the amount of work required for this project is very unclear at
> A>the moment.
> Acctually the definition of these protocols has been taken over by CCSDS
> (ccsds.org). I think they are now in some of the green or blue books
> (cannot remember the color). There is some heavy push in the satellite
> community on moving towards CCSDS protocols so, for sure, there is
> practical value in the corresponding communities. I cannot answer the
> question to what extend an implementation is required. I know that we have
> some activity in the lower layers and that the upper layers are also used
> (file transfer, for example). Don't know about networking and security,
Thanks for the reply. Looks like I will cross this project out from my list.
I have found that there is even a reference implementation of SCPS protocols:
It's usable from FreeBSD too, because they have implemented everything
in userspace, probably to achieve portability. I wonder whether it
would make sense to rewrite it or some parts of it (TCP "performace
enchancing proxy" is the interesting one) for kernel mode.
Theoretically, that should mean better latency, and no data copy
overheads, right? But then again, satellite link bandwidths probably
are too small to make such improvements important.