The rapid rise of the Internet and of data traffic in general are causing network operators to make large investments in high speed packet networks. However, in order to get a return of investments, carriers must offer not only plain bit transport, but also voice, multimedia and converged voice/data services. Therefore high performance QoS packet networks are expected to carry also an increasing share of the traffic of today's circuit switched networks. An evolutionary strategy to achieve carrier-grade services across heterogenous networks is analyzed. The network architecture, protocols, characteristics of key network elements and suitable implementation concepts are discussed. It is shown how the re-use of existing call control capabilities from voice switches and the proper use of commercial IT-platforms as adjuncts achieve maximum flexibility in the migration path and enable network operators to offer all desirable services.

The authors consider some reliability and performance aspects of ATM-based signaling networks. They present ideas on how ATM technology, suitable system concepts, as well as simplified and enhanced protocols could maintain or even improve the reliability level of the existing Common Channel Signaling System No. 7. They also discuss possible scenarios for the interworking of ATM-based signaling networks with existing signaling networks. They also examine the aspect of performance enhancement in terms of reduced delays and increased throughput due to the ATM signaling connections with higher bit rates and protocol simplifications.>