QoS-Aware Self-adaptation of Communication Protocols in a Pervasive Service Middleware

Pervasive computing is characterized by heterogeneous devices that usually have scarce resources requiring optimized usage. These devices may use different communication protocols which can be switched at runtime. As different communication protocols have different quality of service (QoS) properties, this motivates optimized self-adaption of protocols for devices, e.g., considering power consumption and other QoS requirements, e.g. round trip time (RTT) for service invocations, throughput, and reliability. In this paper, we present an extensible approach for self-adaptation of communication protocols for pervasive web services, where protocols are designed as reusable connectors and our middleware infrastructure can hide the complexity of using different communication protocols to upper layers. We also propose to use Genetic Algorithms (GAs) to find optimized configurations at runtime to achieve self-adaption of web service transport protocols (TCP, UDP and Blue tooth), taking into consideration QoS requirements. Our tests show that protocol switching involves little performance overhead and runs efficiently. Our evaluations also show that the proposed approach for achieving self-adaptation for communication protocols is effective where optimized configurations of protocols can be obtained with acceptable performance and quality by GAs.