[Serusers] SIP Books

[Kiko Vives]

Hi all.

I would like to buy a good book about SIP.

I have read in this list that "Internet Communication Using SIP: Delivering
VoIP and Multimedia Services with Session Initiation Protocol" by Henry
Sinnreich and Alan B. Johnston is a really good one.

Does anyone know another better ?

Thanks in advance.

Kiko

PS: please, someone answers my previous post which ask if with NATHELPER +
RTPROXY is possible to establish videoconference sessions and not only audio
sessions and if this is solved with Mediaproxy.

A bunch of thanks !