From: Alex Hudson home@alexhudson.com

I think, but don't quote me ;), that we're actually only talking about one patent here - 5,437,013. 5,265,261 appears to be an earlier version, and at first sight Microsoft appear to have narrowed their claim from the previous version. There is also supposed to be an even earlier original claim, which has now been completely disclaimed - if anyone can find it, it would be interesting (I don't think the UKPTO passed it?).

What the patent appears to be is a claim on raw-mode network access, along the lines of libpcap or something - an efficient way of marshalling streams of data from applications and the network stack to the wire so that it actually makes sense. I would be astonished if there was no good prior art on this; the claim is from ~1993. Even if there is no prior art, I can't believe that it's even vaguely original.

RAW network access has been implemented by Sun in 1986 with:

- Reverse ARP Boot Protocol daemon

- Etherfind (a precursor of Snoop) ... the programs where the ideas have been copied as "tcpdump"

Jörg

EMail:joerg@schily.isdn.cs.tu-berlin.de (home) Jörg Schilling D-13353 Berlin js@cs.tu-berlin.de (uni) If you don't have iso-8859-1 schilling@fokus.gmd.de (work) chars I am J"org Schilling URL: http://www.fokus.gmd.de/usr/schilling ftp://ftp.fokus.gmd.de/pub/unix