A Declarative Profile Model for Qos negotiation

Abstract

In this report we define the semantics of a language for dynamic QoS expressions which can be evaluated at run-time for conformance. We define how expressions can be constructed from atomic expressions termed ’basic profiles’ using composition operators. Two such operators are defined: The sum ( ’+’ ) which corresponds to simple conjunction and component-sum (’Å’) which assume that the operands denote properties of separate environments and therefore must be satisfied separately. Based on those, algorithms for conformance checking any pair of expressions can be developed. Concrete models are typically defined for specific application domains, they define the basic profile space and explicitly establishes conformance relationships between basic profiles. These are essentially sets of axioms from which we can infer conformance.