Do Van Thanh

A service oriented architecture framework for collaborative services

The demand for flexible, efficient and user-friendly collaborative services is becoming more and more urgent as the competition in the current market-oriented arena is getting more intense and fiercer. Enterprises have to be more dynamic in terms of collaboration with partners and even competitors. The service oriented architecture is a promising distributed computing paradigm offering solutions that are extendible, flexible and compatible with legacy systems. This paper proposes and investigates the use of SOA in the construction of collaborative services. The paper starts with a short introduction of the service oriented architecture and then gives a description of collaborative services. A generic model of a collaborative service is analysed to identify the basic collaborative functions. A service oriented architecture framework for collaborative service is presented.

Using the mobile phone as a security token for unified authentication

The number of different identities and credentials used for authentication towards services on the Internet has increased beyond the manageable. Still, the most common authentication scheme is based on usernames and passwords. This is a weak authentication mechanism, which can be broken by eavesdropping on the network connection or by sloppy handling by the users (e.g. re-use of the same password for different services, writing down the passwords on paper etc.). Also, management of user credentials is a costly task for most companies, estimated by IDC to around 200-300 USD pr. user/year. Hence, better solutions for simplified, yet secure authentication, is required in the future. This paper proposes and describes an authentication scheme based on a One-Time Password (OTP) MIDlet running on a mobile phone for unified authentication towards any type of service on the Internet.

A service-oriented architecture framework for mobile services

Service-oriented architectures and service-oriented computing are the most recent approaches aimed at facilitating the design and development of applications on distributed systems. The paper investigates how the construction of mobile services can benefit from the service-oriented paradigm. The paper provides a presentation of the service-oriented architecture. A general discussion of equivalence between service components is then undertaken, in order to enable an analysis of service-oriented architectures for mobile services. The paper proceeds with a mapping of existing mobile services on service-oriented architectures. The requirements of mobile services, which must be taken into consideration in the service-oriented architecture, are identified from a generic model of mobile services. A service-oriented architecture framework supporting mobile services is proposed.

Name resolution in on-demand MANETs and over external IP networks

Common user applications cannot run in mobile ad-hoc networks (MANETs) before a method for name resolution is in place. While the domain name system (DNS) works well on the fixed Internet, it represents a centralized approach to name resolution, which is not suitable for MANETs. This article refines the framework developed for name resolution in MANETs and shows a mechanism for local name resolution can be implemented transparently to the application. It also proposes methods to align local name resolution on the MANET with DNS over external IP networks, forming one integrated method for name resolution. Finally, different strategies for how to store name-to-address mappings on the MANETs are discussed.

Integrated management platform for seamless services provisioning in converged network

With the convergence of IN and IP traditional network management systems have been replaced by a variety of standards. New principles of management have also emerged. Related to these changes new alternative network management techniques are needed. There are a lot of efforts in management protocols improvement based on advanced computer simulation techniques. But, there is a lack in the development of fundamental theoretical models for management architectures. To remedy the situation we develop an analytical modelling tool for the converged network management. More precisely, we implement a queuing model on the application layer to perform effectively a signalling management into both parts of the converged SIP- and IN-based network. We model this distributed management configuration as a finite source queuing model. Furthermore, we evaluate the steady-state performance measures such as expected waiting time and time in system, and present numerical results providing corresponding curves for them.

Strong authentication with mobile phone as security token

The protection of digital identities is getting more and more crucial. The usage of passwords for authentication is no longer sufficient and stronger authentication schemes are necessary. Strong authentication solutions using two identification factors require often an additional device, which could be inconvenient for the user and costly for the service providers. To avoid the usage of additional device, the mobile phone is adopted as security token. This paper provides a study of the various ways the mobile phone can be used as an authentication token towards service providers on the Internet. It starts with discussing the need for a strong authentication scheme, and the motivation for using the mobile phone to improve on several aspects of the current authentication processes. Thereafter, the general architecture for authentication with mobile phones is presented. Several different authentication solutions using the mobile phone as authentication token are then described, where the solutions vary in complexity, strength and user-friendliness. The paper ends with an evaluation of the different solutions, and a discussion of the most probable attacks. A classification of the solutions is also provided, according to defined criteria.

An analysis of service continuity in mobile services

Users are making use of more and more devices like mobile phones, PDAs, laptops, stationary PCs, etc., and it is crucial to provide service continuity not only across heterogeneous networks but also across heterogeneous devices. Users should be able to use services with minimum interruption even when changing devices. This paper provides an analysis of the composition and distribution of generic mobile services. It then addresses the impacts these models have on service continuity across networks, devices and domains.

Service Discovery in Future Open Mobile Environments

Future mobile environment will see the open situation of mobile device that can be connected to several network systems offering heterogeneous sets of services using different names. In addition, the future mobile service can be anything and anybody including end-users can be service providers. This will result to the demand of having a dynamic and efficient service discovery and service matching. The paper discussed on the requirements of future service discovery based on the limitations found in the evaluation of existing service discovery schemes. Finally, the design of a future service discovery solution is proposed.

An analytical approach to the efficient real-time events/services handling in converged network environment

Converged network seamlessly integrates different communications media such as data, voice and multimedia on a single platform. It refers to convergence both types of network and technologies as well as convergence between the different layers of network architecture. In this paper, we examine a priority-based queuing model and perform the mathematical analysis of different media calls processing in converged network environment. We use for this purpose a queuing system model M3/G3/1/NPRP in order to process effectively input jobs/requests (or packets). Tasks within this queuing system get a higher priority if they are handling a real-time event. We present in our paper mathematical results of the expected response and waiting time, and build hypothetical diagrams for the further practical usage in real-time system. A modeling method developed in this paper will be used for the fast configuration and testing of new converged network applications and services.

Quality-driven Service Discovery Techniques for Open Mobile Environments and their Business Applications

In open mobile environments, mobile device may be connected to several network system offering heterogeneous sets of services using different names. The services can be anything and introduced by anybody, which results to have the possibility of having similar service with different names or different services having the same name. The current IEEE 802.21 Media Independent Handover Services facilitate handover across these heterogeneous networks. However, the standard just provides network continuity without ensuring service continuity during the handover. We propose extensions to the MIH, which enable the exchange of service information in addition to network information at handover. This service information constitutes the fundament for a quality-driven service discovery, which is capable of discovering equivalent services and enabling the handover between them. In this paper, the extended MIH handover procedure is explained thoroughly. The additional service information elements are also described. The proposed service discovery system developed on Android is presented and a few use scenarios are given for illustration.