QoS Negotiation in Real-Time Systems and Its Application to Automated Flight Control

ÐReal-time middleware services must guarantee predictable performance under specified load and failure conditions, and ensure graceful degradation when these conditions are violated. Guaranteed predictable performance typically entails reservation of resources and use of admission control. Graceful degradation, on the other hand, requires dynamic reallocation of resources to maximize the application-perceived system utility while coping with unanticipated overload and failures. We propose a model for quality-of-service (QoS) negotiation in building real-time services to meet both of the above requirements. QoS negotiation is shown to 1) outperform ªbinaryº admission control schemes (either guaranteeing the required QoS or rejecting the service request), 2) achieve higher application-perceived system utility, and 3) deal with violations of the load and failure hypotheses. We incorporated the proposed QoS-negotiation model into an example real-time middleware service, called RTPOOL, w...

• Type: Conference
• Year: 1997
• Where: RTAS
• Authors: Tarek F. Abdelzaher, Ella M. Atkins, Kang G. Shin
• Keywords: Admission Control, Embedded Systems, QoS Negotiation, RTAS 1997, Timeliness Qos