Techniques for Hosting Mobile Web Services on Resource Constrained Devices

This thesis concerns hosting web services (WSs) on mobile devices. A number of challenges need to be addressed for hosting web services on such resource constrained devices. These include handling the diversity in the hardware configurations and operating systems for these devices, the execution of resource demanding web service applications and complex WS standards. A multi-dimensional approach has been proposed in this dissertation to address these challenges.;Design time and runtime WS partitioning techniques are proposed to handle complex and resource demanding WS applications. The design time techniques use two graph-based algorithms for WS partitioning: Maximum Offloading Minimum Cost (MOMC) and Cluster based Application Partitioning (CAP). For the runtime WS partitioning technique, multiple execution plans, each of which corresponds to a specific partitioning of the system are determined first and then an appropriate execution plan is selected at runtime by using information on the current system load.;The effectiveness of these proposed techniques is investigated through a system prototype (using sample web services) as well as simulation (using randomly generated application graphs). The experimental results demonstrate that the partitioned systems achieved with the proposed techniques outperform the un-partitioned systems and the partitioned systems using the existing techniques. For fixed load scenarios, the design time WS partitioning techniques are observed to perform the best for a large number of WS clients. Among the design time techniques, MOMC shows the best performance for small to medium size applications whereas CAP exhibits its effectiveness for large sized applications. For systems with a large variability in the number of active WS clients and the workload parameters investigated, the run time partitioning technique outperforms the other techniques.;A web service execution environment (WSEE) that uses lightweight components is devised for hosting web services on mobile devices. The hosted web services can be accessed by multiple WS clients and can support a basic set of WS standards such as SOAP and XML Signature. To support more computationally complex and resource demanding WS standards such as the standards for security and transaction management, a partitioned WSEE is proposed.