Raphael Quinet

Aspect Orientation for Composite Services in the Telecommunication Domain

Telecommunication network operators have specific requirements on services offered through their network, which are frequently independent of the core business logic of the service. As an example, these requirements ensure monitoring of user activities for charging purposes or allow controlling parameters that influence the quality of service. In order to satisfy these demands, services are typically tailor-made to support these supplementary features next to their core business logic. As a result, their implementation becomes tangled and specialized. This is identified as a major obstacle for efficient service composition, because more specialized services are less suitable for being reused in different contexts. This paper describes an approach to introduce concepts of aspect-oriented programming to service composition in order to keep the implementations of telecommunication-specific requirements separated from the core business function of a service.

Cost Control in Service Composition Environments

This paper investigates requirements and proposes solutions for charging of composite services. An analysis of the relations between the service user, service broker and service provider with respect to charging suggests that the price a service broker asks from the user of a composite service is in general decoupled from the price the service broker pays to the service providers of the component services used to create the composite service. Cost control mechanisms as part of the service selection are therefore essential for the service broker. This paper proposes a cost control mechanism based on instantaneous service price prediction.

Multi-Technology Service Composition for the Telecommunication Domain - Concepts and Experiences

Telecommunication networks are service centric and therefore benefit from service composition techniques in accordance to Service Oriented Architecture (SOA) principles. Furthermore, services in the telecommunication domain are subject to specific requirements such as support for end-to-end communication sessions and mechanisms for service interaction across technological borders including telecom, enterprise and Internet services. The presented approach uses a technology-agnostic core composition function, which is comprised of high-level abstraction in the description of heterogeneous services, constraint-based dynamic service selection and step-by-step instantiation of abstract composite application models. In order to better support telecommunication services, these concepts were combined with support for sessions, integration with IP multimedia subsystem (IMS) and support for legacy telecommunication technologies such as Intelligent Networks (IN) [1]. The presented composition approach has become part of products and solutions. This paper reports our experiences regarding the applicability of the technology, efficiency of the composite service development and performance of services composed using this approach.

Scalable service composition execution by means of an asynchronous paradigm

In this paper we describe our findings and experiences with regards to scalable service composition execution. More specifically we detail the process of redesigning our original core for service composition execution to adhere to a more asynchronous, event-driven, non-blocking paradigm. The outcome of this work is an asynchronous core that is scalable; limited by the amount of available memory and not by the number of available processing threads. Another characteristic of the asynchronous core is robustness as system starvation is not possible. Our findings are evaluated with performance results comparing the new asynchronous core to its predecessor. The evaluation focuses on two aspects; throughput and overhead. Our results show that the overhead introduced by service composition is very small: 4 to 12 msec. In addition, the new asynchronous core provides better throughput ranging from +3% to +49% for moderate load and no upper limit for higher load.

Radio Webs - Support Architecture for Mobile Web Access

The speed of Internet access over GSM can be improved by optimizing the performance of TCP/IP connections over the air link, and by using smart proxies for HTTP transfers or other high-level protocols. The goal is to improve the performance as perceived by the user, which implies the minimization of the end-to-end latency. This document describes the setup of GSM data connections and points to a number of possibilities to improve its basic performance. It then takes a more detailed look into WWW access and discusses how a double HTTP proxy can improve the web access over a (very) slow link. This double proxy is made of two parts: a small and simple HTTP proxy on the mobile station and a more complex proxy serving several users from a specific Internet Cellular Access Gateway. The users on the mobile station can configure their usual WWW browser to use the proxy on their computer — the mobile proxy — for accessing Web pages and everything will work as before, except that the overall performance should be considerably better.

Composition in Heterogeneous Service Networks: Requirements and Solutions

Telecommunication networks are service centric and therefore benefit from service composition techniques in accordance to Service Oriented Architecture (SOA) principles. Furthermore, services in the telecommunication domain are subject to specific requirements and topologies of service usage. Examples are services within end-to-end communication sessions and the need to handle service interaction across technological worlds. This includes telecom, enterprise and Internet services. A common service layer for IT and telecommunication needs to be able to handle compositions of services from multiple technological worlds. This paper provides an analysis of the service usage that is typical for various service technologies and it outlines a composition approach that is made to handle heterogeneous composite services.

Blending the telecommunication domain with Web 2.0 services

To stay competitive, operators of modern telecommunication networks are looking for approaches for efficient service creation which would allow for reduction of time-to-market as well as reduction of development and operation costs. Furthermore, they face increasing demand for service interaction across technological borders including telecom, enterprise and Internet services. Telecommunication networks are service-centric and therefore benefit from generic service composition techniques in accordance to Service Oriented Architecture (SOA) principles. In contrast to the IT domain, services in the telecommunication domain are subject to additional requirements such as support for realtime end-to-end communication sessions. The approach presented in this paper uses a technology-agnostic composition functionality characterized by a high-level abstraction in the description of heterogeneous services, constraint-based dynamic service selection and step-by-step execution of composite application models. In order to better fulfill requirements of the telecommunication domain, the approach includes support for end-to-end communication sessions, integration with IP Multimedia Subsystem (IMS) as well as support for legacy telecommunication technologies such as Intelligent Networks (IN) [1]. The presented approach has become part of Ericssons products and solutions portfolio. The high-level overview of the concept and the description of the architecture are illustrated by means of a detailed description for one of the converged applications implemented with this approach.