Service and network providers must be able to satisfy the demands for new services; improve the quality of service; reduce the cost of network service operations and maintenance; control performance; and adapt to user demands. It is essential to investigate different approaches for performing such tasks. One of these approaches is based on policies and the capability of the network to adapt itself to current conditions. With a focus on policy-based networking, this volume addresses the problem of network control and the introduction of policies such as the control of the Quality of Service, security, mobility, performance, mobile and intelligent agents, and traffic engineering. The area