© 2005 SWPS AGENT BASED SEMANTIC GRIDS: RESEARCH ISSUES AND CHALLENGES

Abstra t. The use of agent based servi es in a Computational Grid is outlinedalong with parti ular roles that these agents undertake. Reasons why agents provide the most natural abstra tion for managing and supporting Grid servi es is also dis ussed. Agent servi es are divided into two broad ategories: (1) infrastru ture servi es, and (2) appli ation servi es. Infrastru ture servi es are provided by existing Grid management systems, su h as Globus and Legion, and appli ation servi es by intelligent agents. Usage s enarios are provided to demonstrate the on epts involved. 1. Introdu tion and Related Work. There has been an in rease in interest re ently within the Grid ommunity [11 ℄ towards Servi e Oriented Computing. Servi es are often seen as a natural progression from omponent based software development [6℄, and as a means to integrate dierent omponent development frameworks. A servi e in this ontext may be dened as a behaviour that is provided by a omponent for use by any other omponent based on a network-addressable interfa e ontra t (generally identifying some apability provided by the servi e). A servi e stresses interoperability and may be dynami ally dis overed and used. A ording to [7℄, the servi e abstra tion may be used to spe ify a ess to omputational resour es, storage resour es, and networks in a unied way. How the a tual servi e is implemented is hidden from the user through the servi e interfa e. Hen e, a ompute servi e may be implemented on a single or multi-pro essor ma hine however, these details may not be dire tly exposed in the servi e ontra t. The granularity of a servi e a