UMBC ebiquity
Towards a Well-Behaved Web
January 1, 2005
In order to realize the full potential of the World Wide Web as an open and dynamic network of information, it is important to govern how web entities (e.g., web services and agents) behave in terms of what resources they access (security), how their information is used by others (privacy), whether they are reliable (trust), and how they establish and fulfill social and business obligations and contracts (obligation management).
We propose that a declarative policy-based approach be used, where the norms or rules of ideal behavior of web entities are described in a machine-understandable specification language, and web protocols are modified to include policy exchange, negotiation, compliance checking, and possibly enforcement. Web entities can define policies for several aspects of both their own behavior and the expected behavior of entities they will interact with, including security, privacy, collaboration, and commitments. These policies can be easily updated causing the behavior of the entities to be modified but without affecting the underlying protocols, mechanisms, or architecture. Along with providing the openness required, these policies also provide greater autonomy as they help interacting entities understand each other's capabilities, requirements, limitations, and obligations, infer what their ideal behavior should be, and act accordingly.
In this paper, we describe Rei, a policy specification language represented in an extension of OWL-Lite, which can be used to describe and regulate different kinds of behavior in a wide range of domains. Along with using a rule-based approach for greater expressivity, it also models several aspects of social policies, including consequences of violating policies and conditional permissions that grant certain permissions on the condition that the authorized entities take on certain additional responsibilities. We illustrate the applicability of Rei for policy management of the web through two prototype applications, namely (i) web privacy and (ii) security, privacy, and confidentiality for semantic web services.
TechReport
UMBC
Ebiauity Lab
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