Resumen
Increasingly complex quality-of-service (QoS) requirements in distributed applications require policy-driven middleware devices. Dynamic security requirements, user and component mobility, ad hoc networking of devices, and context-aware computing pose new challenges motivating this approach. A more general view of QoS includes reliability, availability; security, debugging support, real-time guarantees and synchronization of data streams in multimedia delivery middleware structures for implementing complex policies related to these aspects of QoS require mechanisms based on meta-level reflection, aspect orientation and QoS-based allocation of underlying network and operating-system-level resources. A middleware platform may be designed for a specific class of applications for which it provides certain specialized services. Policy-driven middleware requires techniques to validate policies for any conflicts, derivation of suitable policy-enforcement mechanisms and secure installation of these mechanisms in a distributed system. INSET: Policy-driven Middleware for Computer Supported Cooperative...