The need for policies to control calls is justified by the changing face of communications. It is argued that call control requires distinctive capabilities in a policy system. A specialised policy language called APPEL (ACCENT Project Policy Environment/Language) has therefore been developed for this purpose. However the policy language is cleanly separated into a core plus specialisations for various application domains. The paper describes both the foundation and the call control ontologies. Sample policy examples are provided to illustrate use for call control. The paper also presents the policy system architecture in which the policy language is interpreted. The components of the policy system are described, particularly the policy server and the policy wizard.

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This paper is based on the discussion during a panel that took place at the 7 th Workshop on Feature Interactions in Telecommunications and Software Systems in Ottawa, Canada, June 2003. It presents a holistic picture on two paradigms, namely feature and policy, and their intertwining. The guest panelists brought examples from complementary areas and presented their experiences on using the concept of policy for defining features and for treating the feature interaction problem. The intrinsic interactions commonly called policy conflicts within policy-based systems were also discussed. The panelists considered methodological issues, such as the use of deontic logic and the representation of features through policies, as well as industrial applications, such as service provisioning and policy-based management applications for service bundling. They also brought out different views that reflect some disparity between the communities involved in this research.

Organizations constrain the behavior of agents by imposing multiple, often contradictory, obligations and interdictions amongst them. To work in harmony, agents must find ways to satisfy these constraints, or to break less important ones when necessary. In this paper, we present a solution to this problem based on a representation of obligations and interdictions in an organizational framework, together with nn inference method that also decides which obligations to break in contradictory situations. These are integrated in an operational, practically useful agent development language that covers the spectrum from defining organizations, roles, agents, obligations, goals, conversations to inferring and exccuting coordinated agent behaviors in multi-agent applications, One strength of the approach is the way it supports negotiation by exchanging deontic constraints amongst agents, We illustrate this and the entire system with a negotiated solution to the feature interaction problem in the telecommunications industry and a work process coordination example for a manufacturing supply chain.

In future telecommunications systems, behaviour will be defined by inexperienced users for many different purposes, often by specifying requirements in the form of policies. The call processing language (CPL) was developed by the IETF in order to make it possible to define telephony policies in an Internet telephony environment. However, user-defined policies can hide inconsistencies or feature interactions. In this paper, a method and a tool are proposed to flag inconsistencies in a set of policies and to assist the user in correcting them. These policies can be defined by the user in a user-friendly language or derived automatically from a CPL script. The approach builds on a pre-existing logic programming tool that is able to identify inconsistencies in feature definitions. Our new tool is capable of explaining in user-oriented terminology the inconsistencies flagged, to suggest possible solutions, and to implement the chosen solution. It is sensitive to the types of features and interactions that will be created by naive users. This tool is also capable of assembling a set of individual policies specified in a user-friendly manner into a single CPL script in an appropriate priority order for execution by telecommunication systems.