Advanced Service Architectures Research Articles

A novel software approach for service brokering in advanced service architectures

Service brokering considerably enhances advanced service architectures, such as IP Multimedia Subsystem (IMS), since the myriad applications potentially involved in a call or other session are located in the application layer and are separate and large grained. Through effective service brokering — that is, the effective blending and coordinating of services — interaction problems can be controlled and new composite services offering an enriched end-user experience can be provided. How can an effective service brokering capability be realized in a product when it must address needs not yet known? This question instigated the novel software approach (covered by filed Lucent patents) used in the Lucent Service Broker™ product. Adapting techniques used in Web servers and Session Initiation Protocol (SIP) servlet engines, but bringing to the design the special needs for service interaction and blending along with attendant needs for scalability and performance, the Lucent Service Broker was designed as a software engine with a powerful but easy-to-use API for customer programmability. This paper describes the software design of the Lucent Service Broker, particularly focusing on its novel aspects.

Functionality and structure of the service broker in advanced service architectures

This paper discusses the service broker, a function introduced into next-generation networks to manage interactions among applications, to reuse existing applications in a combined fashion, and/or to enable existing applications with capabilities such as presence, location, and policy. With the service broker, a minimal set of applications can be configured in a multiplicity of ways as its elements are brought into play in mix and match arrangements. For the degree of flexibility needed for the service broker to support unique service combinations, the service broker must be programmable. Various functional subcomponents enable these service broker capabilities. These subcomponents include service descriptors, the mechanisms to identify the logic that governs how the applications interact; user and endpoint data managers, the entities that present user-specific and endpoint-specific information; and session contexts, the transient entities that contain the context associated with an instance of call/session or multi-call/session. The session context includes state information and provides multi-session awareness that allows both simultaneous and sequential state-dependent sequential activity to be managed. This paper introduces a lightweight, programmable, Session Initiation Protocol (SlP)-centric service broker architecture and the concept of the “steplet,” which is central to this architecture.

A mobile agent-based advanced service architecture for wireless internet telephony: design, implementation, and evaluation

Internet telephony can be defined as real-time voice or multimedia communications over packet switched networks, including the Internet. The advent of third generation, wireless telecommunications networks will make it much more popular by adding the wireless dimension. Millions of end-users will access Internet telephony services using wireless devices. These end-users will be highly mobile and will change locations very frequently. A key requirement in this environment is universal access. It stipulates that end-users have access to their advanced services from anywhere and from any terminal. Mobile agents can aid in meeting it in an efficient manner. They can carry services and follow roaming end-users. The paper presents the design, the implementation, and the evaluation of a mobile agent-based advanced service architecture for wireless Internet telephony. When a mobile agent carries services, subscription becomes a critical issue. The agent needs to be updated when the end-user subscribes or unsubscribes to services. Our architecture tackles the issue by proposing and evaluating two schemes: agent swapping and on-the-fly updating. Although, wireless Internet telephony is our prime target, the architecture is, to a large extent, independent of the underlying network and therefore applicable to Internet Telephony in general.

Emerging alternatives to today's advanced service architectures for Internet telephony: IN and beyond

Two principal sets of standards are emerging for Internet telephony: H.323 from the ITU-T, and session initiation protocol (SIP) from the IETF. The advanced service architecture that comes with H.323 is rather archaic, and reminiscent of the old days of circuit–switched telephony. The one that comes with SIP is more modern, but has its share of deficiencies. While improvements are being made, alternatives are being sought. Two trends are noticeable in the search for alternatives: the return to the old and well-known intelligent network (IN) architectural framework, and the exploration of more recent approaches, such as mobile agent technology, that go beyond IN. This paper scrutinizes the trends in the search for alternatives to today's ITU-T and IETF advanced service architectures for Internet telephony. We successively review the IN-based architectures that are emerging, and the mobile agent-based architectures that are being explored. Many circuit–switched networks that adhere to the IN architectural framework have been deployed worldwide. The emerging IN-based advanced service architectures may facilitate the reuse of this installed base. They will however fall short when it comes to supporting the wide range of advanced services expected from Internet telephony. Mobile-agent-based advanced services architectures are much more promising, although the technology is not yet mature. Their inherent flexibility can easily help in exploiting to the fullest extent the host of opportunities Internet telephony brings. The return to the IN architectural framework may be economically viable in the short and medium terms. There is however no doubt that it will be imperative to go further in the long term. Mobile agent technology is certainly among the venues worth being explored for going beyond IN.

TINA for services and advanced signaling and control in next generation networks

This article describes solutions that use the Telecommunications Information Networking Architecture and its advanced service architecture and call model, for the definition of services and advanced signaling and control in next-generation networks. It presents both the solutions for extending traditional signaling and/or interacting and interworking with it, and the way the TINA service architecture can constitute an intelligent service platform providing multiple value-added services to the PSTN and the Internet. In each case, the article provides details and examples to demonstrate the case and illustrate the solutions for trendy technologies such as mobile and the Internet.