Resource and Service Discovery

The emerging relevance of mobile computing execution environments for service provisioning is increasing and increasing the importance of mechanisms, tools, and policies to support the dynamic retrieval of resources and service components, i.e., resource/service discovery. Mobility, with its wide spectrum of different types (client mobility, service mobility, code mobility, …) and characteristics (speed, predictability, …), is the crucial property to consider when designing discovery solutions for future mobile computing scenarios. The chapter overviews the main discovery solutions in the literature according to an original taxonomy structured on three different and growing degrees of mobility: i) traditional mobility of discovery clients at service provisioning time, ii) also runtime mobility of discoverable resources, and iii) possibility also for discoverable services (together with their code and reached state) to change their allocation at runtime because implemented as mobile agents. In all three cases, state-of-the-art research activities point out the suitability of exploiting code and/or state mobility techniques to implement discovery solutions for highly mobile deployment scenarios.