Accounting Architecture Involving Agent Capabilities

This paper proposes an Accounting Management architecture, based on TINA principles. Accounting management is defined and positioned in the service provision chain. A relevant computational architecture is proposed and some of the involved computational entities are modeled as agents. A discussion follows on the merits of introducing agents to cater for certain accounting management activities. The ACTS AC325 MONTAGE project provides the main source of the presented work and results. Accounting in the Service Provision Chain The information and communication domains gradually converge, in an evolutionary path characterized by Internet-based access networks and high capacity terminals augmented with integrated multimedia service access capabilities, which can take advantage of the increased network capabilities and emerging service features available to the user. Considering this evolution, future communication systems ambitiously promise to offer a wide variety of highly sophisticated and personalized services over the widest possible coverage area. Several providers are involved in such an ambitious yet realistic service provision scenario in which competition will be mostly played at the service level, with multiple providers offering services over a variety of networks and end systems. TINA1 has defined and documented in the Service Architecture (3) an adequate business model that involves multiple stakeholders, acting in various business roles in the envisaged service provision chain. In a single instance of service provision to a user, several administrative domains may be involved, each controlled by a different stakeholder. Stakeholders may compete and collaborate for attracting the users. The administrative domains may embody several management domains to cater for the necessary management activities, which may span to more than one federated administrative domain. A management domain can be modeled by an information object associated with certain FCAPS (fault, configuration, accounting, performance and security) management functionality (1). Each management domain is governed by one (or more) management policy (such as accounting, security etc.), implemented by manager and managed objects. Additionally, a management domain involves management contexts associated to particular service transactions, setting the management requirements for the delivery of an instance of a service. One of the FCAPS management areas is that of accounting, which is concerned with the collection of resource consumption data for the purpose of capacity and trend analysis, cost allocation, auditing and billing. In capacity and trend analysis, the goal is typically a forecast of future usage. Auditing tasks aim at verifying correctness in billing mechanisms, conformance of resource usage to stakeholder policy established agreements and security guidelines. Cost allocation caters for the appropriate charge assignment to specific resource usage. Billing is responsible for collecting issued cost allocation data, reconstructing missing entries, preparing invoices and distributing them to the corresponding charged domain (4). TINA introduces the concept of Accounting Management Context (AcctMgmtCtxt) which specifies quality and quantity details for the accounting management. AcctMgmtCtxt is a specialization of the management context and constitutes an aggregate of a service transaction. Its purpose is to guarantee that accountability is preserved across a set of activities of distributed objects, which constitute a 1 The Telecommunications Information Networking Architecture (TINA) is an open architecture for future telecommunications and information services. TINA involves a set of principles, rules, and guidelines for constructing, deploying, and operating services. service. Accountability is not defined exactly, but TINA surmises that it is preserving a set of quantities corresponding to the service being received (5). The AcctMgmtCtxt is part of the set-up and wrap-up phases of a service transaction (1). In the setup phase, the user presents the desired accounting schema in the form of AcctMgmtCtxt, which is analyzed and resolved2 with the schema of the provider. The context is then interpreted referring to the service session specification and the accounting environment of the domain (e.g. tariff, billing). The service resources are set following the results of the interpretation. In the wrap-up phase, the service transaction is considered as successfully concluded if the accounting information conforms to the agreed AcctMgmtCtxt (5). The paper presents a general accounting management model and proposes a TINA-based computational architecture that caters for accounting management in a federated context. A discussion then unfolds on the merits of considering agent capabilities in support of certain accounting management functionalities. Relevant concerns are discussed, justifications of choices are presented and expected advantages are advocated. Conclusive remarks complete the paper. Accounting Management Model In the highly evolved and competitive world of communication services provision, accounting management plays a vital role within the operations of each involved stakeholder. Supplementary functionality needs to augment accounting management in order to enable more accurate, efficient and profitable operations for the administrative domain it applies. Based on the above, we have developed an accounting management model, which has served as a basis for the relevant implementation of MONTAGE (2). This model comprises the following processes: • Policy establishment process. This process sets the rules governing the whole accounting management function. It must be able to precisely determine the origin, formation, direction and collection of all actions pertaining to the accounting scope of the particular administrative domain. • Accounting Management Context process. During this process, the context for the accounting management function pertaining to a service session instance is communicated among the appropriate parties, negotiated, finalized and bound for the duration of the service transaction. • Usage process. This process meters the usage of the available resources and creates records in an administrative domain (6). The metering scheme is prescribed by the existing policy and the appropriate accountable resources trigger the metered events. • Charging process. This process collects data generated by the usage process and classifies them into a set of classes relevant to the accounting scheme applicable to the administrative domain. Additionally, the existing tariff function is utilized in order to assign monetary cost to the generated classes. • Billing process. This process is responsible for the collection of charging information, the appropriate indication of the charged entity and the delivery of the issued charge. • Supplementary accounting process. Under this item, add-on capabilities for the accounting management are prescribed. These may concern dynamic behavior of the management domain in order to analyze past and present usage, forecast future demand, dynamically allocate or negotiate applicable tariffs, intelligently perform economic analysis on the service commodities offered, promote when needed service offers. The following figure (fig. 1) depicts these accounting management processes within a multiple stakeholder environment. 2 For a more elaborate description on the accounting schema resolutions, the reader is referred to TINA Accounting Management Architecture (5, p11-12). (Consumer) domain “A” (Retailer) domain “B” (Service provider)