Distributed Self Fault-Diagnosis for SIP Multimedia Applications

In spite of the recent growth in Internet multimedia communications, service availability and voice quality of IP-based multimedia applications still falls behind when compared to traditional PSTN voice services, as shown in a recent study. In contrast to PSTN, the Internet decentralizes network intelligence and allows end user devices and local networks to grow significantly in capability and complexity. Yet, the world is still dominated by a centralized service and management model, as in PSTN. In this model, the authors assume all network elements can be professionally (centrally) managed, a service provider is able to "See" and control every network element, including a user device, and all failures are hard failures thus easily detectable.