Howdy,

Went poking through the IP protocol list the other day and discovered
UDP-Lite. After reading bits of the RFC I'm interested in using this in
an application.

So my question is: How broadly supported is it? Do any OS's have it in
their TCP/IP Stack code by default these days, or does everything need
a patch? A related question: Is the Win32 TCP/IP stack modular like the
linux kernel? Can you shim into it without huge gobs of proprietary
(expensive) libs?

Any appreciated!

-Thanks
-Matt

"shrike@cyberspace.org" <shrike@cyberspace.org> writes:
> Went poking through the IP protocol list the other day and discovered
> UDP-Lite. After reading bits of the RFC I'm interested in using this in
> an application.

The protocol appears to depend somewhat on having an underlying link
layer that does only "partial" error detection (i.e., omitting part of
the frame from the usual FCS computation), and an application that can
deal with partially-corrupt data. Without those things, it's
essentially the same as UDP.

Link layers, at least, that have that property seem to be few and far
between.

> So my question is: How broadly supported is it? Do any OS's have it in
> their TCP/IP Stack code by default these days, or does everything need

I don't know of any deployed implementations. The closest references
I can find are what appear to be experimental versions and research
projects of various sorts:

http://www.inria.fr/rapportsactivite...ics/uid23.html
http://www.rus.uni-stuttgart.de/nks/...?id=31&type=98
http://linux-net.osdl.org/index.php/TODO
http://rohc.sourceforge.net/
http://research.microsoft.com/msripv6/ReadMe.htm

--
James Carlson, KISS Network <james.d.carlson@sun.com>
Sun Microsystems / 1 Network Drive 71.232W Vox +1 781 442 2084
MS UBUR02-212 / Burlington MA 01803-2757 42.496N Fax +1 781 442 1677

Howdy,

Yep, you get no benefit in the core network. Even worse you can't use
IPSec with it without negating error tolerance as a feature.

The obvious application is passing data over IP, stripping the IP
header and dumping UDP lite into a modulator and then into a radio.
Under those circumstances you do get some benefit, particularly if
there is a session layer that does forward error correction.

shrike@cyberspace.org wrote:
> A related question: Is the Win32 TCP/IP stack modular like the
> linux kernel? Can you shim into it without huge gobs of proprietary
> (expensive) libs?


Look into the Windows Socket Service Provider Interface (SPI). You can
do at least some of that with a layered service provider.