Projects
Next Generation Wireless Mobile Cellular-Based Networks Theme
Project Title: Subscription-Based Policy Control Framework For 3GPP IP Multimedia Subsystem (IMS)
IP Multimedia Subsystem (IMS) is defined by 3GPP (3rd Generation Partnership Project) as the all-IP based core network solution capable of providing real time multimedia services independent of access network. It is an access-independent and packet-based IP connectivity and service control architecture that enables various types of multimedia services for end-users using common Internet-based protocols. The Policy and Charging Control (PCC) architecture is proposed in the 3GPP’s Release 7 to combine the functionalities which were specified and identified separately in previous releases. However, this new architecture has limitations and problems. For example, all the policy controls are carried out at the network level with the emphasis on QoS mapping for different access networks and does not take subscriber’s information into consideration. Other problems such as no participation of core network elements also contribute to its imperfectness.
In this research project, we aim at designing a subscription-based policy control framework for 3GPP IMS. The framework will play works in organizing the subscription data, identifying the policy, stipulating the policy control process, interpreting, managing and enforcing the corresponding policy complemented to the current PCC. The framework will provide a subscription-centric approach to the PCC architecture and enables flexible policy definitions based on subscription on application level. The core elements, which are defined in the framework to facilitate policy design and to achieve the flexibility, are designed to qualify the subscribers and thus greatly enhance the network customization reflected by the capabilities of defining various flexible policies based on different subscriber policy control requirements.
Project Title: Hybrid Call Admission Control Policy for Next Generation Mobile Networks
In this research project, we aim at investigating the following: (a) How to manage resources and control end-to-end QoS for mobile users accessing multimedia services over heterogeneous networks, given that each network posses its own resource management schemes and policies? (b) How will a wireless environment in the context of heterogeneity provide strict QoS guarantees for real-time applications?, and (c) How will the networks provide at least a gradual change in resource availability in order to let the applications adapt as users roam across different technologies. We plan to evaluate and build on previous solutions that we proposed for wireless cellular networks and distinguish and investigate the modifications required to make them more appropriate for heterogeneous environments. To this end, we will investigate the use of adaptive CAC scheme and bandwidth adaptation techniques in heterogeneous wireless networks that support multimedia traffic.
Project Title: Dynamic Bandwidth Allocation for Mobile WiMAX
WiMAX technology is designed to support a wide range of multimedia applications, (voice, video and data) in an IP based, seamless mobile environment. A WiMAX network has a limited set of resources available to meet the demands of users. A dynamic bandwidth allocation and admission control schemes are needed in order to distribute wireless resources such that the total carried traffic can be increased even in a saturated network. In order to accomplish the conflicting goals of increasing the total carried traffic and meeting minimum quality of service demands from users, we are developing an efficient method to provide a fast technique of allocating bandwidth. Bandwidth is allocated based on the benefit noticed by users this is accomplished by the use of utility functions. Each WiMAX connection class is associated with a utility function, which represents the adaptive characteristics of this application type. In addition, admission control scheme is investigated to ensure that new and incoming handoff connections are given fair bandwidth allocation. We plan to use method such as the search tree to predict what the outcome of admitting a new connection to the network.
Wireless Mobile Sensor Networks Theme
Project Title: Routing in Three Dimensional Sensing-Covered Network
Sensor network is a promising technology that can be used to reduce the impact of several disasters (e.g. Tsunami). This would be achieved by providing update to date information about a region, and thus, providing early salvation and early evaluation of a possible aftermath. The surrounding medium for a region can be of any kind (e.g. water). In this research project, we are interested in deploying sensor networks in underwater environments. This would need several issues to be improved. We would only focus on topology, coverage, and routing by relying heavily on graph theory. For topology issue, our interest falls into improving topologies (e.g., Unit Disk Graph (UDG)) in sensor networks. Thus, we are interested in producing new topologies that can avoid UDG’s drawbacks. Moreover, to increase the level of connectivity of such topology, there is a need for achieving fully sensing-covering regions. In addition, many existing works do not clearly illustrate how coverage is obtained, thus, we would be focusing on constructing robust coverage techniques for obtaining fully covered regions. For routing in sensing-covering regions, we would be interested in implementing new position-based routing protocols that can outperform other existing protocols in terms of several design factors such as network dilation, Euclidean dilation, and power dilation.
Project Title: Cluster-based Routing Protocol for Mobile Sensor
This project proposes a mobility-aware routing protocol, using zone-base information and a cluster-like communication between nodes. The protocol involves aspects related with clusters formation, zones and routes maintenance, same as mobility and communication between sensor nodes.
It has been studied in many research projects and papers, that the hierarchical routing and specifically the clustering mechanisms make a big improvement in Wireless Sensor Networks (WSN) and help to reduce the energy consumption and the overhead created when all the sensor nodes in the network are sending information to the central data collection point or base station. However, most of the routing and clustering protocols currently used or proposed for WSN assumed that the nodes are stationary, which makes them invalid to be used in applications like habitat monitoring (animal tracking) or search and rescue, where the static nature of sensors is not real.
One of the reasons for the sensors to be taken as stationary is because that assumption facilitates the simplification of the clustering protocols, making them have a very low overhead. It also avoids having to manage the mobility patterns of the sensors and allows saving more energy, since the localization information that the network has to manage is non existent. This project’s goal is to design a routing protocol for high density and mobile wireless sensor networks, where the clusters are formed based on the mobility of sensors, but the information overhead caused by that mobility is not very high. The clustering and routing protocol also must include mechanisms to manage the route maintenance necessary because of the broken routes and the re-routing processes.
