In recent decade, the topic of MANET privacy has been flourished. Privacy is the main aim of the traffic analysis attacks. Indeed, an adversary intercepts network traffic in order to infer sensitive information about network traffic characteristics such as the identities of communicating parties, location of nodes data transmission rate and motion pattern of nodes, in traffic analysis attacks. This may lead to severe threats in security-sensitive applications. In the other hand, privacy is considered as one of the most important security features in the specific applications of MANET including military networks and search and rescue operations. Concealing the routing information from adversary and even legitimate nodes is an effective method to resist against traffic analysis attack. Although the secure routing for MANETs has been extensively studied, traffic analysis attacks are still not well addressed. So, providing anonymous routing protocols i.e. routing protocols which include anonymity services is quite important. Using these protocols is necessary to resist against to traffic analysis attack in order to hiding some information such as the real identity of network nodes and network topology. The aim of this thesis is presenting an improved algorithm in order to defend against traffic analysis attacks. To this end, at the first, traffic analysis attacks and their countermeasures in MANET have been studied. These have been justify; TEXT-INDENT: 18pt; MARGIN: 0cm 0cm 0pt; unicode-bidi: embed; DIRECTION: ltr" Keywords: Mobile Ad Hoc Network, Traffic Analysis Attack, Anonymity, Privacy, Anonymous Routing
