It is a very well organized textbook. Authors first explain reasons (economic and technical) for IP-3G convergence. Major conceptual differences between IP and mobile communications, on standardization processes, network approaches, connectivity, design approaches are compared in order to highlight difficulties for such a converged solution. Then three major issues are examined in details: session management & SIP protocol, QoS and Mobility Management (macro and micro). Last, authors discuss what is next: All-IP 3G and beyond.
This is an excellent book about the subject, for its coverage, simplicity and appropriate references and 'further readings' lists given at the end of each chapter.