Showing papers on "Hybrid Wireless Mesh Protocol published in 2011"

Energy optimization based path selection algorithm for IEEE 802.11s Wireless Mesh Networks

Abstract: It is everyone's dream to have network connectivity anywhere at all times. This dream can only be realized provided there are feasible solutions that are put in place for the next generation of wireless works. Wireless Mesh Networks (WMNs) configures itself and because of its cost effectiveness, it is therefore seen as a solution for the next generation networks. However, this field still has a lot of limitations and the main constrain is that the energy of the nodes is very limited, especially when the network is deployed in rural areas where electricity is a scares resource. This research therefore presents an energy optimization based path selection algorithm for IEEE 802.11s WMNs which is aimed at addressing the above mentioned constrains. As a newly proposed standard specifically designed for WMN, the IEEE 802.11s does not consider energy conservation as a priority in its protocol. As a result, the main goal for this research is that paths with enough energy for transmission in the network must be selected when transmitting packets. Our simulation results obtained from the experiments prove that there is a substantial increase with regard to the network's operational time when energy is considered by the protocol used in IEEE 802.11s.

Performance Comparison between IBC-HWMP and Hash-HWMP

Abstract: In this paper we have implemented the Hash technique to provide security in HWMP (Hybrid Wireless Mesh Protocol). Then after, we compared the Hash based HWMP against IBC (Identity Based Cryptography) based HWMP. This study has been carried out to show the great benefits of the IBC technique in securing HWMP. Results have shown that, IBC-HWMP outperforms the hash-based HWMP in terms of overhead and delay. According to the obtained results the use of IBC with HWMP provides a greate level of security with light overhead.

A light weight security scheme for HWMP protocol using Elliptic Curve technique

Abstract: In this paper we have implemented the ECDSA (Elliptic Curve Digital Signature Algorithm) technique to provide security in HWMP (Hybrid Wireless Mesh Protocol). The motivation behind the use of ECDSA is that it is integrated into the IEEE P802.11s/D4.0 standard. We have used the ECDSA technique to secure control message in HWMP, namely PREQ (Path Request) and PREP (Path Reply). In these Control messages, we are interested only by mutable fields (i.e. fields that change during control packet exchange). Simulation results show that the ECDSA-HWMP does not too much a long overhead compared to the orignal HWMP.

A new MIMC routing protocol compatible with IEEE 802.11s based WLAN mesh networks

Abstract: Utilizing multi-interfaces and multi-channels (MIMC) is essential in increasing capacity and performance of emerging wireless mesh networks. However, the current IEEE 802.11s draft which is a standardization activity of the WLAN based mesh network does not sufficiently consider these capabilities. This may lead to poor performance of the network in terms of throughput and scalability. In this paper, first we analyze the misbehavior of the current standard especially in the path selection process. Then, we propose a new routing protocol that is suitable for the multi-interface and multi-channel environment. The proposed scheme selects high throughput paths based on channel diversity information and reduces the broadcast overhead of control messages. Moreover, it is fully compatible with Hybrid Wireless Mesh Protocol (HWMP) which is the default routing protocol proposed in the current standard. Interestingly, in the simulation study, we observe that the network performance increases even though only a partial number of nodes are equipped with the proposed scheme.

An interference-aware routing metric for Wireless Mesh Networks

Abstract: In Wireless Mesh Networks (WMNs), most routing metrics measure losses using the |direct| broadcast approach that incurs traffic overhead. On the other hand, the |indirect| approach requires the measurement of contention and interference levels. Unfortunately, the two known interference models (protocol and physical) are inapplicable on real-world implementations. This work presents an adaptation of the physical interference model that relies on a probabilistic frames arrival model and can be implemented. This adaptation allows the design of a new interference-aware routing metric. This latter is described and compared to ETX and IEEE 802.11s Airtime using a real-world indoor pre-IEEE 802.11s Wireless Mesh test-bed.

Session-oriented Adaptive Routing for improving path stability in WLAN based mesh networks

Abstract: The IEEE 802.11s standard is designed to support multi-hop mesh networking between WLAN devices. It features the HWMP (Hybrid Wireless Mesh Protocol) as its default path selection protocol which combines the proactive tree building mode and the on-demand path selection mode. The proactive mode can periodically maintain the lowest link cost route to the root node, but poses the path instability problem, where the path is unnecessarily changed when the path is updated. As a result, the performance of the network is degraded. To alleviate this problem, we propose the Session-oriented Adaptive Routing (SOAR) protocol, which recognizes each data session and prevents path switching while the data session is in progress. To achieve this, we do not switch the existing path even though the link cost may be higher than the new path, unless the potential throughput gain of the new path is considered better than the pre-determined threshold. Moreover, the new path with lower link cost is also stored and used when a new data session is initiated. We have conducted preliminary simulation studies via the ns-3 to evaluate the performance of the proposed scheme.

Tree-based Proactive Routing Algorithm Based on Hybrid Wireless Mesh Protocol

Abstract: Wireless Mesh Network (WMN) is an emerging broadband wireless access technology to support different application scenarios of wireless access. IEEE 802.11s standard defines a default routing algorithm, called Hybrid Wireless Mesh Protocol (HWMP). HWMP combine tree-based proactive routing mode with on-demand routing mode. In this paper, the proactive routing mode to reduce network overhead and enhance network performance is improved. It can be seen from the simulation results that the improved algorithm reach a better performance in the packet delivery rate, average end-to-end delay and throughput.