Farhat Anwar

A simulation based performance comparison of routing protocol on Mobile Ad-hoc Network (proactive, reactive and hybrid)

Mobile Ad-hoc Network (MANET) is a collection of wireless mobile nodes which dynamically forms a temporary network without the use of any existing network infrastructure or centralized administration. Recently, there has been a tremendous growth in the sales of laptops, handheld computers, PDA and portable computers. These smaller computers nevertheless can be equipped with megabytes/gigabytes of disk storage, high-resolution color displays, pointing devices and wireless communications adapters. Moreover, since many of these small computers operate for hours with battery power, users are free to move without being constrained by wires. To support such type of scenario MANET has been designed. MANET has several characteristics such as, dynamic topologies, bandwidth-constrained, variable capacity links, energy-constrained operation and limited physical security. There are three types of routing protocols in MANET such as Proactive, Reactive, and Hybrid. In this paper, a detailed simulation based performance study and analysis is performed on these types of routing protocols over MANET. Ad Hoc On-Demand Distance Vector (AODV), and Dynamic MANET On-demand (DYMO) routing protocol (reactive), Optimized Link State Routing protocol (OLSR) (proactive) and Zone Routing Protocol (ZRP) is (hybrid) have been considered in this paper for the investigation and their relative performance is reported.

Performance study of hybrid Wireless Mesh Protocol (HWMP) for IEEE 802.11s WLAN mesh networks

Wireless Mesh Network (WMN) have been envisioned as an important solution to the next generation wireless networking which can be used in wireless community networks, wireless enterprise networks, transportation systems, home networking and last-mile wireless internet access. Many proprietary mesh solutions were developed by individual vendor but in order to interoperability; IEEE forms a task group called IEEE 802.11s to develop an integrated mesh networking solution. Hybrid Wireless Mesh protocol (HWMP) and airtime metrics as default routing protocol and routing metrics set by the task group. There is few test bed and many simulation studies have been done to evaluate the performance of the HWMP protocol with the assumption of unique type of flow with fixed packet size and packet rate. However, real networks carry a diverse application (video, voice, FTP, Email etc) with different characteristics (packet size, data rate). In this paper, we are investigated and analyzed the performance of HWMP protocol under such heterogeneous application characteristics.

ENFAT-AODV: The fault-tolerant routing protocol for high failure rate Wireless Sensor Networks

As more and more real Wireless Sensor Networks (WSN) applications have been tested and deployed over the last decade, the research community of WSN realizes that several issues need to be revisited from practical angles, such as reliability and availability. Furthermore, fault-tolerance is one of the main issues in WSNs since it becomes critical in real deployed environments where network stability and reduced inaccessibility times are important. Basically, wireless sensor networks suffer from resource limitations, high failure rates and faults caused by the defective nature of wireless communication and the wireless sensor itself. This can lead to situations, where nodes are often interrupted during data transmission and blind spots occur in the network by isolating some of the devices. In this paper, we address the reliability issue by designing an enhanced fault-tolerant mechanism for Ad hoc On-Demand Distance Vector (AODV) routing protocol used in WSN called the ENhancement of FAult-Tolerant AODV (ENFAT-AODV) routing protocol. We design and implement a backup route scheme by creating a backup path for every node in the network. When a node gets failure to deliver the data packet through the main route, it immediately employs the backup route to become a new main path for the next data packet delivery to reduce a number of data packets dropped and to maintain the continuity of data packet transmission in presence of some faults (node or link failures). Furthermore, with high failure rate, this proposed routing protocol improves the throughput and the average End-to-End delay and decrease the control packet load in the network. Consequently, the reliability, availability and maintainability of the network are achieved. The simulation shows that proposed routing scheme is better than the AODV routing.

An integration of mobile motion prediction with dedicated solicitation message for seamless handoff provisioning in high speed wireless environment

Wireless mobility seems to be transforming the communication industry, shifting the momentum from Internet access to broadband wireless access. This technology-shifting has been expected to provide a better communication services in return. The ability to transfer communication at extremely high speeds and the ability to stay connected during a fast movement speed should always be applicable for the upcoming and future technology. This involves addressing the challenge of maintaining the quality of service (QoS) in wireless high speed movement environment. This paper presents a method employing dedicated solicitation message for supporting fast mobile nodes switching process while moving between heterogeneous access routers (AR). Simulation of the proposed method show substantial performance improvement for one of the mobile IPs enhancement scheme known as SIGMA. The proposed method has been integrated with our previous enhancement method on SIGMA known as mobile motion prediction and the performance of the integrated approach demonstrates an overall improvement.

A simple and effective technique for human verification with Hand Geometry

This paper presents a new hand geometry based human verification technique which is efficient, simple, fast, easy to handle and cost effective compared to other verification techniques. Hand geometry is a popular biometric type in verification process. This hand geometry based verification comprises of two main attributes, (1) feature extraction by image processing and (2) feature learning by artificial neural network (ANN). For feature learning, distance based nearest neighbor (DBNN) algorithm has been applied. Using this approach, experimental results show 99.11% total success rate (TSR), 2.97% false acceptance rate (FAR) and 0% false rejection rate (FRR) (using 250 samples). A comparison is made between proposed method and published alternative hand geometry based methods at the end of this paper. The experimental results demonstrate that the proposed method outperforms the existing methods.

Investigating mobile motion prediction in supporting seamless handover for high speed mobile node

While witnessing the rapid development in the world of wireless communication, it is highly expected that the next generation of wireless network to be quickly adapt with the high Quality of Service (QoS) requirements and demands from mobile wireless users especially in real time and multimedia applications. Mobile IPv6 has been declared to be unsuitable for managing the mobility of end users running such stringent QoS specifications since the resulting latency and packet loss rate during handover are too high. To address the issue, various new and state-of-the-art protocols have been designed and developed, particularly to meet the demand for mobile Internet users. In this paper, we have investigated the effectiveness of mobile motion prediction technique in providing seamless handoff for high speed wireless environment where mobility prediction purpose is to obtain a priori information regarding the next Access Router (AR) the mobile node will move to. It was shown that the prediction information is found to be very helpful in establishing an advance connection with the new AR so that the high handoff latency and packet loss rate can be greatly reduced.

Prediction of received signal power and propagation path loss in open/rural environments using modified Free-Space loss and Hata models

This paper describes a modification of the Free-Space and Hata formulae for the prediction of received signal power, PR and propagation path loss, LP, in two cellular mobile radio systems (CMRS), in the Northern Nigeria. Measurements of PRs were taken with a Cellular Mobile Radio test Receiver (Sagem OT 160), in some selected open/rural environments, when the receiver was being moved away from the base stations along the propagation paths. LPs were then obtained from values of measured PRs using an appropriate expression. A close comparison of measurement values and computed values from the free-space and Hata formulae revealed that direct application of these formulae is inappropriate for the prediction of these parameters in the region of investigation, as computed values fell short significantly from the corresponding measured values. Consequently, some correction factors have been introduced to both models and these have produced results which closely matched the measured values.

A Simulation Based Performance Analysis of Reactive Routing Protocols in Wireless Mesh Networks

Wireless Mesh Networks (WMNs) have recently gained a lot of popularity due to their rapid deployment and instant communication capabilities. WMNs are dynamically self-organized, self-configured and self-healed, with the nodes in the network automatically establishing an ad hoc network and preserving the mesh connectivity. Due to the increasing interest on wireless mesh architectures, a new IEEE working group, 802.11s has recently created. The purpose of this working group is to standardize the architectures and protocols that support both broadcast/multicast and unicast delivery between Access Points (APs). In this paper, a detailed simulation based performance study and analysis is performed on the reactive routing protocols over such kind of networks. Ad Hoc On-Demand Distance Vector (AODV), Dynamic Source Routing (DSR) and Dynamic MANET On-demand (DYMO) routing protocol are considered as the representative of reactive routing protocols. The performance differentials are investigated using varying traffic load and number of source. Based on the simulation results, how the performance of each protocol can be improved is also recommended.

Enhancement of handoff latency reduction mechanism of mobile internet protocol version 6 (MIPv6)

MIPv6 is envisioned for next generation networks to achieve ubiquitous and seamless communications for its wide address spaces and many additional features. However, MIPv6 is not widely deployed due to handoff latency and other limitations leading to packet loss and Quality of Service (QoS) degradation for real time applications such as audio and video streaming. MIPv6 handoff latency can be categorized into layer 2 (L2) and layer 3 (L3) delays that includes link layer establishment delay, movement detection delay, address configuration delay and binding update or registration delay. Movement detection delay and address configuration including Duplicate Address Detection (DAD) in layer 2 and layer 3 respectively consume the highest time of the total delay. Therefore, an optimal solution is needed to reduce the delays in both layers. In order to reduce these handoff latencies, two solutions are proposed to focus all the delays both in L2 and L3. The first solution is the fuzzy logic technique based network awareness to reduce movement detection delay especially the scanning time in layer 2 in heterogeneous networks. The second solution is parallel DAD (PDAD) to reduce address configuration time in layer 3. Both solutions benchmarked with OMNeT++ simulator show improvements over standard MIPv6 networks. The overall handoff reduced from 1300ms to 500ms applying fuzzy logic technique at L2 and PDAD mechanism in L3 that combines 60% improvements.

A Parallel Duplicate Address Detection (PDAD) mechanism to reduce handoff latency of Mobile Internet Protocol version 6 (MIPv6)

Next Generation Networks (NGN) are envisioned to be fully Internet Protocol (IP) based so that users can experience high quality and ubiquitous communication. In order to realize this, Internet Engineering Task Force (IETF) is taking advantage of Mobile Internet Protocol version 6 (MIPv6) because it has more suitable features than MIPv4. However, MIPv6 is not widely deployed due to handoff latency and other limitations. This causes packet loss and degrades the Quality of Service (QoS) for real-time applications. MIPv6 handoff latency includes link layer establishment delay, movement delay, address auto-configuration delay and binding update/registration delay. Duplicate Address Detection (DAD) is performed during address auto-configuration which takes around 70% of the time for the total handoff procedures. In order to reduce this handoff latency, a Parallel DAD (PDAD) model is proposed for reducing packet loss. The key idea behind this model is that a Mobile Node (MN) solicits for a router advertisement (RA) in parallel to its neighbor routers before leaving the previous point of attachment.