Wireless Mesh Networks

Routing Across Wired and Wireless Mesh Networks: Experimental Compound Internetworking with OSPF

by Juan Antonio Cordero Fuertes

Co-authored with Matthias Philipp and Emmanuel Baccelli.
Accepted for publication in the 8th IEEE International Wireless Communications and Mobile Computing Conference (WCMC 2012).

Best Effort versus Spectrum Markets: Wideband and Wi-Fi versus 3G MVNOs?

by Lee McKnight

Weaving a New 'Net: A Mesh-Based Solution for Democratizing Networked Communications

by Aram Sinnreich

Published in "The Information Society," 2011. Coauthored with Nathan Graham and Aaron Trammell.

Although the Internet is largely decentralized in its commu- nication and social patterns, its technical and... more Although the Internet is largely decentralized in its commu- nication and social patterns, its technical and regulatory appara- tuses are highly centralized and hierarchical. Consequently, digital communications are vulnerable to a degree of surveillance and censorship that would be unthinkable in traditional social are- nas, threatening “Internet freedom” and cyberliberties in both democratic and politically repressed societies. We believe a new architecture is required in order to protect the continuance of civil liberties in networked society. In this article, we propose 10 “social specifications” describing the requirements of such a network, and outline an architecture called MondoNet that meets these specifica- tions using ad hoc, wireless mesh networking technologies. We also address the legal and technical challenges facing the MondoNet project, and anticipate future developments in this field.

Controle de admissão para chamadas VoIP em redes mesh sem fio

by Edjair Mota

Neste trabalho apresentamos um protótipo de controle de admissão para chamadas VoIP em redes mesh sem fio IEEE... more Neste trabalho apresentamos um protótipo de controle de admissão para chamadas VoIP em redes mesh sem fio IEEE 802.11g, integrado ao protocolo de roteamento OLSR, que estima  a interferência intra-fluxo e o tempo de ocupação do canal com tráfego VoIP e BE (Best effort), para decidir se uma nova chamada pode ou não ser aceita na rede. Nossa proposta também regula a transmissão do tráfego BE para que ele não inviabilize o uso do VoIP. Nossa premissa é a possibilidade de haver chamadas VoIP com qualidade quando a rede não está congestionada, assim, o controle de admissão proposto deve evitar que a entrada de novas chamadas VoIP na rede consuma excessivamente recursos dos nós e cause degradação nos fluxos já estabelecidos.

Comparative analysis of routing protocols for VoIP in a Wireless Mesh Backbone: a user perspective

by Edjair Mota

In this work we select AODV, OLSR and HWMP routing protocols and focus on how they can affect the Quality of user... more In this work we select AODV, OLSR and HWMP routing protocols and focus on how they can affect the Quality of user Experience (QoE) with respect to VoIP on a wireless backbone. We calculated QoE by using a reviewed version of the E-model. Since that parameter is strongly correlated with some stochastic network variables it presents stochastic behaviour too. So, we discuss important issues needed to estimate QoE based parameters in a trusty way. Results showed that the average QoE kept acceptable only under AODV routing as the number of VoIP traffic was increased in the network.

Towards an Efficient Header Compression Scheme to Improve VoIP over Wireless Mesh Networks

by Edjair Mota

Header compression techniques can improve the speech quality of VoIP applications. However, its deployment over... more Header compression techniques can improve the speech quality of VoIP applications. However, its deployment over wireless mesh environments may not offer much improvement, since the wireless and multi-hop characteristics of such a network impose a high packet loss rate. In this work, we propose a new approach for header compression, using packet aggregation to cooperate with the header compression scheme. Simulation results show that the new cooperative approach can decrease significantly the packet loss, impacting positively on the speech quality.

Composite Metric for Quality of Service Routing in Wireless Mesh Networks

by Edjair Mota

To support multimedia applications like Voice over Internet Protocol (VoIP) traffic in Wireless Mesh Networks, routing... more To support multimedia applications like Voice over Internet Protocol (VoIP) traffic in Wireless Mesh Networks, routing algorithms should determine a route satisfying Quality of Service requirements, such as packet loss, minimum bandwidth and end-to-end delay. In this paper, we propose an end-to-end metric function consisting of an objective method to predict quality of service. Our metric computes end-to-end delay and loss packet values and find an optimal path estimating speech quality service.

Influence of Routing Protocol on VoIP Quality Performance in Wireless Mesh Backbone

by Edjair Mota

In this paper we focus on the following question: how routing protocols, working under different channel conditions,... more In this paper we focus on the following question: how routing protocols, working under different channel conditions, can influence the human perceived quality of VoIP calls in a wireless mesh backbone? In order to respond this question, we propose a study case where we analyze two routing approaches in a 802.11 Wireless Mesh Backbone, namely, reactive AODV and proactive OLSR. We calculated the voice speech quality by making use of a reviewed version of ITU-T E-Model proposed in previous work. Results obtained from highly credible stochastic simulation environment, also described in this paper, showed that AODV performs better in very hostile mediums while OLSR presents better results when more friendly mediums take place.

Defaulting a wireless radio

by IT Ambassador Ted Green

Author: IT Ambassador Ted Green

Towards a Sharing Protocol for Wireless Grids

by Lee McKnight

CORFUNET: A MESH NETWORK PROVIDING WIRELESS SERVICES AT METROPOLITAN LEVEL

by Andreas Floros

A. Pateli, A. Floros, K. Oikonomou and E. Magkos, “CorfuNet: A Mesh Network Providing Wireless Services at Metropolitan Level”, In Proc. of the IADIS International Conference - Wireless Applications and Computing 2008, Amsterdam, July 2008, pp. 124 – 128.

This paper discusses the technology and commercialization challenges of a research initiative intended to establish a... more This paper discusses the technology and commercialization challenges of a research initiative intended to establish a wireless metropolitan network for the city of Corfu. Key wireless mesh networking issues are discussed and value for the potential service providers and users of the network is specified. The network development builds on advanced features of wireless mesh networks, like multi-channel and multi-radio operation, connectivity to a fixed network infrastructure through multiple links and general purpose applications support, which overcome many of the limitations that are currently imposed by wireless ad-hoc networks. The proposed network is designed to provide apart from broadband Internet access a number of sophisticated services to the citizens, tourists and business visitors of the island. To assure viability and expansion for the CorfuNet initiative, the present study discusses scenarios on two alternative business models, namely the collaborative and the single provider models, differentiated on the basis of the network’s owner.

AR-TP: An adaptive and responsive transport protocol for wireless mesh networks

by Enrico Natalizio

Wireless meshing has been envisioned as the economically viable networking paradigm to build up broadband and... more Wireless meshing has been envisioned as the economically viable networking paradigm to build up broadband and large-scale wireless commodity networks. Several different mesh network architectures have been conceived by both industry and academia; however many issues on the deployment of efficient and fair transport protocols are still open. In this paper, an adaptive and responsive transport protocol (ARTP) is proposed for WMNs in order to fairly allocate the network resources among multiple flows, while minimizing the performance overhead. Compared to the classical end-to-end rate control mechanisms, an hop-by-hop congestion control approach is designed to keep track of dynamic multi-hop network characteristics in a responsive manner. In addition, a coarse-grained end-to-end reliability algorithm is integrated with the proposed hop-by-hop congestion control mechanism to provide packet level reliability at the transport layer. Performance evaluation via extensive simulation experiments show that the AR-TP protocol achieves high performance in terms of network throughput and fairness.

A reactive and dependable transport protocol for wireless mesh networks

by Enrico Natalizio

In the last few years, several different mesh network architectures have been conceived by both industry and academia;... more In the last few years, several different mesh network architectures have been conceived by both industry and academia; however, many issues on the deployment of efficient and fair transport protocols are still open. One of these issues is rate adaptation, that is, how to allocate the network resources among multiple flows, while minimizing the performance overhead. In order to address this problem, in this paper, we first define an analytical framework for a very simple topology. The model allows us to study the performance of an adaptive and responsive transport protocol when the effect of the lower layers are ignored. The mathematical approach alone does not represent a feasible solution, but it contributes to determining the strengths and weaknesses of our proposal. The main novelty of the proposed solution is that the congestion control approach is based on a hop-by-hop mechanism, which allows nodes to adapt their transmitting rates in a distributed way and to keep track of dynamic multi-hop network characteristics in a responsive manner. This is in contrast with classical literature solutions, founded on an end-to-end support. Anyway, to ensure the reliability, a coarse-grained end-to-end algorithm is integrated with the proposed hop-by-hop congestion control mechanism to provide packet level reliability at the transport layer. Performance evaluation, via extensive simulation experiments, shows that the proposed
protocol achieves a high performance in terms of network throughput.

Multi-Hop Relaying Techniques with OSPF on Ad Hoc Networks

by Juan Antonio Cordero Fuertes

Co-authored with E. Baccelli and P. Jacquet.
Published in the 4th IEEE International Conference on Sensor Networks and Communications (ICSNC), held in Porto (Portugal) in September 2009.

A Theoretical Model for Analyzing the Impact of Jitter-based Techniques on Flooding over Wireless Ad Hoc Networks

by Juan Antonio Cordero Fuertes

Co-authored with P. Jacquet and E. Baccelli.
INRIA Research Report n. 7701

Jitter is used in wireless ad hoc networks to reduce the number of packet collisions and the number of transmissions.... more Jitter is used in wireless ad hoc networks to reduce the number of packet collisions and the number of transmissions. This is done by scheduling random back-off for each packet to be transmitted and by piggybacking multiple packets in a single transmission. This technique has been standardized by the IETF in RFC 5148. This paper investigates on the impact of the standardized jitter mechanism on network-wide packet dissemination – i.e. flooding, an important component for many protocols used today. A novel analytical model is introduced, capturing standard jitter traits. From this model is derived accurate characterization of the effects of jittering on flooding performance, including the additional delay for flooded packets on each traversed network interface, the reduction of the number of transmissions over each network interface, and the increased length of transmissions, depending on jitter parameters. This paper also presents an analysis of the use of jitter in practice, over an 802.11 wireless link layer based on CSMA. The analytical results are then validated via statistical discrete event simulations. The paper thus provides a comprehensive overview of the impact of jittering in wireless ad hoc networks.

Wireless Grids: Assessing a New Technology From a User Perspective

by Lee McKnight

Wireless grids--distributed resource sharing by mobile, nomadic, and fixed devices.

by Lee McKnight

Co-authored by Lee W. McKnight, HJames owison, & Scott Bradner (2004). IEEE Internet Computing, 8(4), 24-31.

Wireless Grid Networks and Virtual Markets

by Lee McKnight

Enhanced Multi-radio AODV in Hybrid Wireless Mesh Networks

by Maaly Awad Hassan

Authors: Maaly Awad Hassan, Hatem Mahmoud Hamad
Journal of Media and Communication Studies (JMCS)
Vol. 3, No. 5, pp.188-197|May 1, 2011

Utility based channel assignment mechanism for multi radio mesh networks

by Maryam Amiri Nezhad

published in Proceedings of the 8th ACM international workshop on Mobility management and wireless access- 2010

We address the channel assignment problem in a multi-radio mesh network that involves assigning channels to radio... more We address the channel assignment problem in a multi-radio mesh network that involves assigning channels to radio interfaces for eliminating the effect of wireless interference. Due to the insufficient number of frequency channels and available radios per node, interference is still present which limits the available bandwidth on wireless links and eventually decrease the achievable throughput. In this paper we investigate the effect of considering the diverse delivery probability of the wireless links on the channel assignment solutions. We show that it is possible to classify the wireless links and omit some of them to benefit from a more diverse-channel solution. We propose a new channel assignment aiming to minimize the interference over high performance links. Finally a performance study is carried to assess the effectiveness of our proposed algorithm. Evaluations show that the multi-channel network obtained from our proposed algorithm achieves significant improvement in terms of reducing the interference and increasing the network capacity.