Hi all, Thanks to this mailling list, I've been able to use successfully the fifo of SER to register a UA by this way. The problem is that I have a lot of UA using the fifo to register, so I have to create a receipt fifo for each command I send to the SER Fifo. So I think the socket could be a more convenient way to bypass the creation of so many receipt fifo. I found no documentation related to the syntax of the socket, and I'd like to know if somebody can explain me how I can use this socket for registration purpose. Thanks very much, Rodrigue