Faouzi Zarai

Adaptive call admission control in 3GPP LTE networks

SUMMARY In this article, we propose new methods to reduce the handoff blocking probability in the 3rd Generation Partnership Project Long Term Evolution wireless networks. This reduction is based on an adaptive call admission control scheme that provides QoS guarantees and gives the priority of handoff call over new call in admission. The performance results of the proposed schemes are compared with other competing methods using simulation analysis. Simulation results show the major impact on the performance of the 3rd Generation Partnership Project Long Term Evolution network, which is reflected in increased resource utilization ratio to (99%) and in the ability in satisfying the requirements of QoS in terms of call blocking probability (less than 0.0628 for Voice over IP service) and dropping probability rate (less than 0.0558).Copyright

Multi-criteria dynamic access selection in heterogeneous wireless networks

Service delivery in a heterogeneous wireless network environment requires the selection of an optimal access network. Indeed, the selection of a non-optimal network can result in undesirable effects such as higher costs in terms of new call blocking and handoff call dropping rates or poor service experience. Network selection in such an environment is influenced by several factors related to network conditions, application parameters, user preferences and terminal performances. This paper, first, describes a new architecture which allows a resource-efficient management that aims at selecting the “best-suited” network interface for each application. Second, it presents a comprehensive decision making process to rank candidate networks for service delivery to the application. The proposed scheme is based on a decision process using the TOPSIS method when solving the multi criteria analysis. The wireless networks in this model represent the alternatives, while the network and application parameters (bandwidth, Received Signal Strength, velocity support, load factor and power consumption cost) are considered as the criteria for determining the optimal network.

Secure handoff protocol in 3GPP LTE networks

To provide secure 3GPP LTE-WLAN interworking, Extensible Authentication Protocol-Authentication and Key Agreement (EAP-AKA) is used. However, EAP-AKA has several vulnerabilities such as disclosure of user identity, man-in-the-middle attack, Sequence Number (SQN) synchronization, and additional bandwidth consumption. Therefore, in this paper, we propose new re-authentication protocol for wireless 3GPP LTE. The proposed protocol guarantees stronger security, mutual authentication, and resistance against many attacks. The suggested solution proves its effectiveness following the studies of simulation which carried out according to different criteria handoff latency, loss and blocking rate.

Heterogeneous Wireless Networks: Configuration and Vertical Handoff Management

Vertical handoff is one of the most important issues for the next generation heterogeneous wireless networks. However, in many situations, unbeneficial vertical handoffs occur across intersystem heterogeneous networks cause network performance degradation. Therefore, we propose a novel configuration architecture that can be deployed in the next generation of wireless networks. Second, we propose a predictive and adaptive Vertical Handoff Decision Scheme that optimizes the handoff initiation time as well as selection of the most optimal network. The proposed vertical handoff decision algorithm considers the technology type as well as the Signal to Interference Ratio (SIR), the Mobile Station (MS) velocity, the user preferences, the applications requirements and the terminal capabilities as the most important factors to make vertical handoff decision. In order to minimize handoff costs, the proposed decision algorithm uses the dwell timer concept. The handoff costs are analyzed in terms of unnecessary and unbeneficial handoffs rate.The simulation results show that the reduction of unnecessary handoffs proposed in our vertical handoff decision scheme reduces the handoff blocking probability, the packets loss rate and the handoff overhead

Power and Delay-aware Multi-Path Routing Protocol for Ad Hoc Networks

Mobile Ad Hoc Networks (MANETs) also called mesh networks, consist of a large number of mobile nodes that communicate with each other in the absence of any fixed infrastructure or centralized administration. The principle characteristics of MANET are the dynamic topology and the limited battery power of mobile nodes. The discharge of the battery causes many problems such as the loss of the packets and the re-initialization of route discovery which leads to lot of bandwidth consumption, increase in the delay and decrease in the throughput. In this paper, we propose a new power and delay aware routing protocol for wireless Ad Hoc networks. The goal of our proposed routing protocol is not only to find more stable paths from a source to a destination node in terms of remaining life time of battery, but also to find multi-paths that satisfy Quality of Service (QoS) requirements, given in terms of delay and bandwidth. To evaluate our proposed routing protocol (PDMRP), an extensive simulation study is performed using the NS-2 simulator. We show through simulation that our proposed routing protocol called Power and Delay aware Multi-path Routing Protocol (PDMRP) outperforms the Stable Path Routing Protocol based on Power Awareness (SPR) and the Modified Adhoc On-Demand Distance Vector (MAODV) routing protocols in terms of throughput, end-to-end delay, and loss rate. We modify the AODV protocol in NS-2 simulator so that it supports the energy module. We add the energy class to the relay and destination nodes. Therefore, the life time of each node in this protocol decreases when it sends or receives a packet. This modification is made on the AODV protocol to become similar to the two other routing protocols (The three protocols support the energy module).

A novel vertical handoff decision making algorithm across Heterogeneous Wireless Networks

Heterogeneous Wireless Networks communication is a combination of various heterogeneous networks. With their complementary characteristics, incorporation of these technologies in the same network in order to provide a full coverage to mobile users causes several challenges such as handover decision making and mobility management. A good handoff decision should avoid unnecessary handovers, which increase the computational network load. In this paper, we present a novel approach for Handover decision making in the context of heterogeneous wireless network. The aim of the proposed scheme is the selection of the most suitable radio access network for each application. Simulation results show that the proposed approach can guarantee QoS requirements and reduce the blocking probability of new and handoff calls.

Design and analysis of secure host-based mobility protocol for wireless heterogeneous networks

Mobility protocols allow hosts to change their location or network interface while maintaining ongoing sessions. While such protocols can facilitate vertical mobility in a cost-efficient and access agnostic manner, they are not sufficient to address all security issues when used in scenarios requiring local mobility management. In this paper, we propose a new scheme that makes Host Identity Protocol (HIP) able to serve as an efficient and secure mobility protocol for wireless heterogeneous networks while preserving all the advantages of the base HIP functions as well. Our proposal, called Heterogeneous Mobility HIP (HMHIP), is based on hierarchical topology of rendezvous Servers (RVSs), signaling delegation, and inter-RVS communication to enable secure and efficient network mobility support in the HIP layer. Formal security analysis using the AVISPA tool and performance evaluation of this method are provided; they confirm the safety and efficiency of the proposed solution. HMHIP reduces handover latency and packet overhead during handovers by achieving registration locally.

Vertical handoff management for next generation heterogeneous networks

The next generation heterogeneous networks represents a new technology that will enable seamless integration of various wireless access systems, and targeted to support various sophisticated and Quality of Service (QoS) constraining applications, such as high-speed data services, video applications, and multimedia services. To guarantee different QoS requirements for diverse traffic types, while at the same time maintaining fair and high utilization of wireless resources, an efficient mobility management, specifically the vertical handoff (inter system handoff), is essential in the next generation wireless networks. In this paper, first we propose a novel scheme for reducing handoff delay using the concepts of Received Signal Strength (RSS) and thresholds management. Second, we propose a new secured IP assignment protocol. Finally, performance of the new scheme for reducing handoff delay has been studied exhaustively through simulation.

An efficient design and validation technique for secure handover between 3GPP LTE and WLANs systems

Future generations wireless systems, which integrate different wireless access networks together, will support a secured seamless mobility and a wide variety of applications and services with different quality of service (QoS) requirements. Most of the existing re-authentication protocols during vertical handover still have certain limitations such as man in the middle, eavesdropping and session hijacking attacks, and unacceptable delay for real time applications. In this article, we propose two re-authentication schemes to secure handover between 3GPP LTE and WLANs systems: Initial Handover Re-authentication Protocol, and Local Re-authentication Protocol. The second proposed protocol is executed locally in a WLAN network without contacting the authentication server of the home network for credentials verification. In fact, after a successful execution of the Initial Handover Re-authentication Protocol, the local key (LK) is shared between USIM and the authentication server of the WLAN. It is then used for securing handover and traffic in WLAN networks. Performance evaluation results obtained using simulation analysis show that the proposed re-authentication protocol enhances handover parameters such as handover latency, handover blocking rate and packet loss rate. Additionally, the proposed enhanced fast re-authentication protocol has been modeled and verified using the software AVISPA and is found to be safe.

A novel media independent handover-based approach for vertical handover over heterogeneous wireless networks

The key purpose for seamless mobility and service continuity between heterogeneous wireless networks is the handover. Vertical handover management is one of key challenges in such environment. To deal with some of these challenges, an IEEE 802.21 media independent handover MIH framework has been standardized. The main purpose of this standard is to offer a general interface for the handover by abstracting the link layer intelligence to higher layers. However, there still exist a number of limitations in MIH architecture. In this paper, a new architecture of improved MIH is presented to perform vertical handover between wireless heterogeneous networks. We focused on interworking architecture between wireless local area network and long term evolution advanced network with the use of MIH signaling to define an efficient vertical handover. A performance analysis model for the proposed MIH-based vertical handover is derived. Analysis results show that the proposed method can be easily deployed in present multimedia service networks. Copyright