From: "Rob Jarratt" <robert.jarratt at ntlworld.com> No. It uses a TCP connection. Each buffer received from the device driver is sent along on the TCP connection with a 2-byte length prefix, and that is it. So no DDCMP underneath. OK cool. Little-endian? [Paul Koning] If you want to really make your head spin, imagine DMP/DMV emulation (DDCMP multipoint). I've never really understood this. Is it a broadcast net, or what? I'm pretty sure I have a pair of DMVs in this mess somewhere... John Wilson D Bit