A Session Aware Admission Control Scheme for Next Generation IP Services

Under overload condition, a processing server contributes to the poor QoS through sustaining heavy request queuing delays and prolonged processing time. Admission control is a well known mean to prevent a server overload. Most state of the art research advocate session oblivious mechanisms where the dropping of the requests pertaining to an accepted session can occur at any time during the session lifespan. From an operator perspective, this means that the server, which seems to sustain a high throughput, is in reality wasting its resources on failed or on reduced QoS sessions. In this work, we advocate an innovative architecture for session aware admission control of an offered IP traffic to a cluster-based server. The proposed system is enhanced with means for maximizing the useful throughput in terms of completed sessions per unit of time. It particularly achieves an improved responsiveness and a better stability. Finally, it is open to adapt to any multiple-flow based NGN service such as voice over IP or streaming video.