QoS-Aware Scheme for Mobility Management and Adaptive Resource Reservation in 4G Wireless Networks

Introduction

The future-focused networks are designed to satisfy the growing users’ need for bandwidth-hungry applications and rich media services. These networks are expected to integrate advanced built-in QoS functionalities and to meet great challenges related namely to high capacity, seamless handoff, intelligent resource reservation, real time service delivery and low latency.

These IP based networks, called 4G networks, are capable of supporting and handling the technological heterogeneity through the integration of various access networks ranging from cellular networks such as (UMTS, Universal Mobile Terrestrial Service) to wireless access networks such as (WLANs, Wireless Local Access Networks and Ad’hoc networks) within a scalable and innovative platform.

Enhancing the capability of these networks to deliver better services for these new applications through the provision of end-to-end QoS is becoming a key challenge and a condition of the success of the fourth generation of mobile wireless networks.

QoS guaranties are particularly required for real time and streaming multimedia applications and services in networks where network capacity is limited. This requirement arises specially with the need for traffic management and when congestion, jitter and latency are likely to affect services availability. But, because of the high mobility constraints and the lack of coordination between management entities of different portions of the heterogeneous networks, the fulfillment of end-to-end requirements have no guarantees. This why guarantying seamless mobility and QoS for end-to-end delivery of services over heterogeneous networks, where more than one management entity exists is still an open issue.

Promising and successful future 4G frameworks will overcome the aforementioned shortcomings and provide personalized user services which demands higher understanding of user’s expectations.

Therefore, key features of 4G will be, besides QoS consistency, the implementation of user personalization, deploying heterogeneity in terms of network, terminal and services, evolutionary design of devices and personalized content on mobile devices.

Several research initiatives have been proposed in the literature to address QoS optimization through the enhancement of resource reservation mechanisms and the mobility management across heterogeneous access networks. Some of these works were interested in proposing general frameworks for QoS optimization either by estimating user requirements and peak time of services utilization to save the bandwidth/cost factors (Abbasi, A.A., Iqbal, J. and Malik, A. N. (2010)) or by designing a multiobjective optimization framework which provides a clear and comprehensive description of different options and solution to achieve an optimal network planning (Gordejuela-Sanchez, F., Juttner, A. and Zhang, J. (2009)).

Other works have addressed the QoS aspects in heterogeneous networks from an architectural point of view. Aiash, M., Mapp, G. and Lasebae, A. (2011) proposed a QoS signaling mechanism to be implemented by the Y-Comm architecture as a potential 4G framework. The proposed mechanism is designed to handle heterogeneity in the sense that it introduces new functional modules and interfaces to be run on different network entities. Providing end to end QoS over heterogeneous networks through an extensive 4G architecture is approached by Iancu, B., Dadarlat, V. and Peculea, A. (2010). This architecture which uses an hierarchical approach to organize link bandwidth is based on agreed SLAs and SLSs between autonomous management entities and is characterized by the creation of a new abstraction layer with complex functions called convergence layer and availing the bandwidth organization. All these contributions were innovative in term of potential scenarios and architectures for the 4G networks but their main shortage is that they were merely descriptive and did not provide analysis of the benefits provided schemes in term of end user QoS parameters.