Interworking Architectures in Heterogeneous Wireless Networks: An Algorithmic Overview

The scarce availability of spectrum and the proliferation of smartphones, social networking applications, online gaming etc., mobile network operators (MNOs) are faced with an exponential growth in packet switched data requirements on their networks. Haven invested in legacy systems (such as HSPA, WCDMA, WiMAX, Cdma2000, LTE, etc.) that have hitherto withstood the current and imminent data usage demand, future and projected usage surpass the capabilities of the evolution of these individual technologies. Hence, a more critical, cost-effective and flexible approach to provide ubiquitous coverage for the user using available spectrum is of high demand. Heterogeneous Networks make use of these legacy systems by allowing users to connect to the best network available and most importantly seamlessly handover active sessions amidst them. This paper presents a survey of interworking architectures between IMT 2000 candidate networks that employ the use of IEFT protocols such as MIP, mSCTP, HIP, MOBIKE, IKEV2 and SIP etc. to bring about this much needed capacity

Network-Assisted Handover for Heterogeneous Wireless Networks using IEEE 802.21

The IEEE 802.21 is a standard for enabling handover in heterogeneous wireless networks. Published in January 2009, it defines protocols and messages for mobile-to-node and node-to-node communication in a technology-neutral and flexible manner. The need arises because of the widespread diffusion of different technologies for wireless communications (e.g., WiFi, WiMAX, LTE) coexisting in the same geographical area. Even though the number of multi-radio multi-technology mobile devices is increasing significantly, there are no open solutions in the market to enable efficient inter-technology handover. As is often the case with communication standards, the structure of the required components, the procedures, and the algorithms are left unspecified by the IEEE 802.21 standard so as to promote competion by differentiation of equipment capabilities and services. The contribution of this thesis is two-fold: i) a design and an implemenation of the Media Independent Information Service (MIIS) server; and, ii) a solution to enable network-assisted handover using the IEEE 802.21 standard, aimed at reducing the handover latency and the energy consumption of mobile devices due to scanning. The MIIS server has been fully implemented in C++ under Linux. In order to perform testbed evaluations, all the required components have been implemented, as well, within an open source framework for IEEE 802.21 called ODTONE. Modifications to the latter have been performed for optimization and fine tuning, and for extending those functional modules needed but not fully implemented. For a realistic evaluation, Linux-based embedded COTS devices have been used, equipped with multiple IEEE 802.11a and IEEE 802.11g wireless network interface cards. This has required additional development for kernel/user space binding and hardware control. Testbed results are reported to show the effectiveness of the proposed solution, also proving the MIIS server scalability

A Seamless Vertical Handoff Protocol for Enhancing the Performance of Data Services in Integrated UMTS/WLAN Network

The Next Generation Wireless Network (NGWN) is speculated to be a unified network composed of several existing wireless access networks such as Wireless Local Area Network (WLAN), Global System for Mobile (GSM), Universal Mobile Telecommunications System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX), and satellite network etc

Acta Universitatis Sapientiae - Electrical and Mechanical Engineering

Series Electrical and Mechanical Engineering publishes original papers and surveys in various fields of Electrical and Mechanical Engineering

Virtualisation d'une plateforme de gestion de contexte

Depuis son apparition, le Cloud Computing a motivé différents acteurs du secteur des technologies de l’information à créer de nouveaux services virtuels. Le Cloud Computing apporte beaucoup d’avantages comme la personnalisation, le paiement au besoin ou encore l’effet d’avoir une élasticité infinie. Les systèmes CA sont des systèmes intelligents qui peuvent changer de comportement dépendamment du contexte dans lequel ils se trouvent. Ce type de système est le genre de système que l’utilisateur final préfère, car il anticipe ses besoins et s’y adapte. Pour avoir, un bon système CA, il faut avoir une bonne base de source d’informations. Ces informations de base permettent à ces systèmes d’être plus précis pour identifier leur contexte actuel. Les réseaux de capteurs sans fil sont une riche source d’information, car ils offrent une information diversifiée et en grand nombre. Notre projet consiste à virtualiser les systèmes CA en utilisant les réseaux de capteurs sans fil. Notre première contribution consiste à décomposer les systèmes CA en blocs fonctionnels. La deuxième contribution est la proposition d’une architecture de gestion de contexte qui permet la composition et le déploiement de services CA dans le nuage. Cette architecture est validée à travers le prototypage et les tests. Notre dernière contribution est la proposition d’une méthodologie de dimensionnement de ces blocs fonctionnels

A Seamless Vertical Handoff Protocol for Enhancing the Performance of Data Services in Integrated UMTS/WLAN Network

The Next Generation Wireless Network (NGWN) is speculated to be a unified network composed of several existing wireless access networks such as Wireless Local Area Network (WLAN), Global System for Mobile (GSM), Universal Mobile Telecommunications System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX), and satellite network etc