Anais - Engenharia de Redes de Comunicação - UnB

A New Scheme for Anonymous Communication in Wireless
Mesh Networks
Joarley Moraes 1 , Roberto Araújo 2 , Antônio Abelém 2
1 Instituto de Tecnologia – Universidade Federal do Pará (UFPa)
Belém – PA – Brasil
2 Instituto de Ciências Exatas e Naturais – Universidade Federal do Pará (UFPa)
Belém – PA – Brasil
{joarley,rsa,abelem}@ufpa.br
Abstract. Wireless Mesh Networks (WMN) have rapidly evolved as a promising
solution for broadband communication. However, security issues as the user’s
anonymity have been an obstacle for their wide deployment. Wu and Li proposed
a scheme to provide anonymity in WMN, but their scheme has drawbacks. In
this paper we present a new scheme, based on some of WuLi’s principles, to
provide anonymous communication in WMN. The solution overcomes previous
drawbacks and is more effective than the former one.
1. Introduction
Wireless Mesh Networks (WMN) is a self-organized and self-configured network
paradigm where mesh nodes operate distributively as host and router. WMNs have became
very popular due to their many inherent advantages such low-cost, easy maintenance,
robustness, and reliable and high-speed network coverage. Such network technology
are undergoing rapid progress and has been deployed in a variety of application in
personal, campus, and metropolitan areas [Akyildiz et al. 2005]. A WMN can be rapidly
deployed, for example, in a small city, so that the inhabitants can share a satellite connection.
In such a scenario, each household works as a mesh node and thus has to be
equipped with Wireless devices. A gateway router,
a centralized entity, is responsible for granting Internet access to the households. Mesh
nodes communicate to each other and to the gateway usually in multi-hop style. When
the communication end is out of range, the data has to transverse a series of other nodes
which will act as intermediate forwarders.
Security and privacy issues, however, are the current main obstacles to the wide
deployment of this technology. Privacy is specially important because of the inherent
public and distributed nature of the WMN channel. Source anonymity is one of the most
relevant privacy properties. Users in a mesh network access the Internet in different context
for services like web-surfing, e-mail, Internet banking, e-commerce, and so on. These
communication may contain several sensitive user’s information, such as personal identities,
activities, location informations, financial data, etc. If those information are disclosed
by attackers, the user’s privacy is compromised. In addition, when such an information
are further correlated to user’s identity, more severe consequences may occur.
In this work, we focus on protecting mesh nodes anonymity against traffic analysis
and flow tracing attacks. In particular, we review a protocol proposed by Wu and Li in
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