Bassel R. Arafeh

Bandwidth borrowing-based QoS approach for adaptive call admission control in multiclass traffic wireless cellular networks

SUMMARY This paper proposes a QoS approach for an adaptive call admission control (CAC) scheme for multiclass service wireless cellular networks. The QoS of the proposed CAC scheme is achieved through call bandwidth borrowing and call preemption techniques according to the priorities of the traffic classes, using complete sharing of the available bandwidth. The CAC scheme maintains QoS in each class to avoid performance deterioration through mechanisms for call bandwidth degradation, and call bandwidth upgrading based on min–max and max–min policies for fair resource deallocation and reallocation, respectively. The proposed adaptive CAC scheme utilizes a measurement-based online monitoring approach of the system performance, and a prediction model to determine the amount of bandwidth to be borrowed from calls, or the amount of bandwidth to be returned to calls. The simulation-based performance evaluation of the proposed adaptive CAC scheme shows the strength and effectiveness of our proposed scheme. Copyright

A multilevel partitioning approach for efficient tasks allocation in heterogeneous distributed systems

This work addresses the problem of allocating parallel application tasks to heterogeneous distributed computing resources, such as multiclusters or Grid environments. The proposed allocation scheme is based on a multilevel graph partitioning and mapping approach. The objective is to find an efficient allocation that minimizes the application completion time, subject to the specified constraints pertinent to the application and system environment. The allocation scheme consists of three phases; the clustering phase, the initial mapping phase and the refinement and remapping phase. The scheme introduces an efficient heuristic in the clustering phase for contracting (coarsening) large size application graphs to the number of processors, called the VHEM method. An initial mapping technique based on a tabu-search approach has been introduced as a basis for the process of refinement and remapping phase. The simulation study shows that the VHEM coarsening heuristic can achieve optimal or near-optimal communication, compared to the HEM method, when the ratio of the number of tasks to the number of processors exceeds a threshold value. The simulation study shows that those optimal or near-optimal VHEM-coarsened graphs have an effect of generating very efficient mappings, when they are compared to the HEM-coarsened graphs.

An adaptive bandwidth borrowing-based Call Admission Control scheme for multi-class service wireless cellular networks

This work describes an adaptive Call Admission Control (CAC) scheme for multi-class service wireless cellular networks. The proposed scheme uses complete sharing approach of the available bandwidth among all traffic classes. The proposed adaptive CAC is achieved through call bandwidth borrowing and call preemption techniques based on the priorities of the traffic classes. The CAC scheme achieves the QoS in each class through mechanisms for call bandwidth degradation, and call bandwidth upgrading based on Min-Max and Max-Min policies for fair resource deallocation and allocation. The simulation results of the proposed adaptive CAC scheme show the strength and effectiveness of our proposed scheme compared to other schemes.

Impact of physical and virtual carrier sensing on the route discovery mechanism in noisy MANETs

In cellular consumer devices, one of the limiting factors for efficiency is that of overhead on the network layer that effects on the performance of the network. A substantial design issue is that, with cellular consumer devices, the discovery phase of the routing process, when attempting to establish a mobile ad hoc network, a high demand is placed on the network layer. Hence, a challenge for the designer is to reduce this demand, thus increasing overall device availability. Routing algorithms, and hence the performance of the networks are adversely affected by inefficient carrier sensing methods which can lead to increasing packet loss within the network environment. In this paper, the effect of physical and virtual carrier sensing on the route discovery mechanism has been identified and this paper suggests that choosing a suitable carrier sensing threshold in a high density and noisy mobile ad hoc network yields a better performance than if the default value is used1.

EMGGR: an energy-efficient multipath grid-based geographic routing protocol for underwater wireless sensor networks

Routing in underwater wireless sensor networks (UWSN) is an important and a challenging activity due to the nature of acoustic channels and to the harsh environment. This paper extends our previous work [Al-Salti et al. in Proceedings of cyber-enabled distributed computing and knowledge discovery (CyberC), Shanghai, pp 331–336, 2014] that proposed a novel multipath grid-based geographical routing (MGGR) protocol for UWSNs. The extended work, EMGGR, viewed the network as logical 3D grids. Routing is performed in a grid-by-grid manner via gateways that use disjoint paths to relay data packets to the sink node. The algorithm consists of three main components: (1) a gateway election algorithm; responsible for electing gateways based on their locations and remaining energy level (2) a mechanism for updating neighboring gateways’ information; allowing sensor nodes to memorize gateways in local and neighboring cells, and (3) a packet forwarding mechanism; in charge of constructing disjoint paths from source cells to destination cells, forwarding packets to the destination and dealing with holes (i.e. cells with no gateways) in the network. The performance of EMGGR has been assessed using Aqua-Sim, which is an NS2 based simulator for UWSNs. Results show that EMGGR is an energy efficient protocol in all simulation setups used in the study. Moreover, EMGGR can also maintain good delivery ratio and end-to-end delay.

Effect of physical and virtual carrier sensing on the AODV routing protocol in noisy MANETs

In cellular consumer devices today, one of the limiting factors behind efficiency is that of battery life. The challenge facing cellular consumer device designers is that the discovery phase of the routing process when attempting to establish a mobile ad hoc network tends to put the highest strain on the battery of the device. Such routing algorithms tend to be affected by carrier sensing which has lead to increasing packet loss within the network environment. This paper is concerned with studying the performance of Ad hoc On demand Distance Vector (AODV) based on physical and virtual carrier sensing as well as the effect of those carriers on the route discovery.

Impact of the noise level on the route discovery mechanism in noisy MANETs

In mobile consumer devices, today, one of the limiting factors behind efficiency is that of battery life. The challenge facing mobile consumer device designers is that the discovery phase of the routing process when attempting to establish a mobile ad hoc network tends to put the highest strain on the battery life of the device. Such routing algorithms tend to be affected by the presence of noise resulting in increased packet loss within the network environment. This paper is concerned with studying the effect of noise level on route discovery mechanism in the ad hoc on demand distance vector (AODV) routing protocol for mobile ad hoc networks. In this paper, a performance analysis of route discovery in AODV is presented based on noise level.

PARALLEL ROUTING IN MOBILE AD-HOC NETWORKS

This paper proposes and evaluates a new position-based Parallel Routing Protocol (PRP) for simultaneously routing multiple data packets over disjoint paths in a mobile ad-hoc network (MANET) for higher reliability and reduced communication delays. PRP views the geographical region where the MANET is located as a virtual 2-dimensional grid of cells. Cell-disjoint (parallel) paths between grid cells are constructed and used for building pre-computed routing tables. A single gateway node in each grid cell handles routing through that grid cell reducing routing overheads. Each node maintains updated information about its own location in the virtual grid using GPS. Nodes also keep track of the location of other nodes using a new proposed cell-based broadcasting algorithm. Nodes exchange energy level information with neighbors allowing energy-aware selection of the gateway nodes. Performance evaluation results have been derived showing the attractiveness of the proposed parallel routing protocol from different respects including low communication delays, high packet delivery ratios, high routing path stability, and low routing overheads.

GEGR: A grid-based enabled geographic routing in Wireless Sensor Networks

Wireless Sensor Networks (WSNs) provide high promises to a wide spectrum of application areas. However, routing packets in WSNs is still facing many obstacles, due to the special characteristics of WSNs. In this work, we propose an energy-efficient and low cost geographic routing algorithm for dense WSNs, called Grid-based Enabled Geographic Routing (GEGR). The proposed algorithm relies on the construction of a 2-D logical grid in the geographical region in which the sensor nodes are deployed. Packet forwarding is handled in each grid cell by an elected gateway node. The packet forwarding process depends on the relative location of the destination cell with respect to the source, and the geographic direction of forwarding. The proposed scheme limits the use of broadcasting in the WSN to the process of gateway election, and the process of constructing and maintaining the table of neighboring gateways in adjacent grid cells. Our simulation results show the effectiveness of our routing scheme and its ability to achieve network scalability compared to on-demand routing protocols.

A unified fault-tolerant routing scheme for a class of cluster networks

Large cluster systems with thousands of nodes have become a cost-effective alternative to traditional supercomputers. In these systems cluster nodes are interconnected using high-degree switches. Regular direct interconnection network topologies including tori (k-ary n-cubes) and meshes are among adapted choices for interconnecting these high-degree switches. We propose a generalized fault-tolerant routing scheme for highly connected regular interconnection networks and derive conditions for its applicability. The scheme is based on the availability of efficiently identifiable disjoint routes between network nodes. When routing paths become faulty, alternative disjoint routes are identified and taken. The methods used to identify the routing paths, to propagate failure information, and to switch from a routing path to another incur little communication and computation overhead. If the faults occur reasonably apart in time, then packets are efficiently routed along paths of minimal or near-minimal lengths. In the unlikely case where several faults occur in a short period of time, the scheme still delivers packets but possibly along longer paths. The proposed scheme and its properties are first presented in general terms for any interconnection topology satisfying certain derived connectivity conditions. The applicability of the general scheme is then illustrated on examples of well known regular topologies satisfying the derived connectivity conditions including the binary hypercube, the k-ary n-cube and the star graph networks.