Contribution to securing wireless mesh networks

A wireless mesh network (WMN) comprises of mesh access points (MAPs)/mesh routers and mesh clients (MCs), where MAPs are normally static and they form the backbone of WMNs. MCs are wireless devices and dynamic in nature, communicating among themselves over possibly multi-hop paths, with or without the help of MAPs. Security has been a primary concern in order to provide protected communication in WMNs due to the open peer-to-peer network topology, shared wireless medium, stringent resource constraints and highly dynamic environment. These challenges clearly make a case for building multi-layer security solution that achieves both wide-range protection and desirable network performance. In this thesis, we attempt to provide necessary security features to WMNs routing operations in an efficient manner. To achieve this goal, first we will review the literature about the WMNs in detail, like WMN’s architecture, applications, routing protocols, security requirements. Then, we will propose two different secure routing protocols for WMNs which provide security in terms of routing, data and users as well. The first protocol is a cross-layer secure protocol for routing, data exchange and Address Resolution Protocol (ARP) problems (in case of LAN based upon WMNs). Our protocol is a ticket-based ad hoc on demand distance vector (TAODV) protocol, a secure routing protocol that is based on the design of the Ad Hoc on demand distance vector (AODV) protocol. Due to the availability of a backbone, we incorporate the Authentication Server (AS) for the issuance of tickets which are further used for secure routing, transfer of public keys and MAC addresses in one single step. By incorporating the public keys, source and destination can easily generate their shared secret key based upon Fixed Diffie-Hellman key exchange protocol for data encryption and decryption. Our protocol is secure against both active as well as passive attacks. The second proposed protocol is to “achieve user anonymity in WMNs”. This protocol is also ticket-based protocol. The ticket is issued by Network Operator (NO) which provides user anonymity, user authentication and data confidentiality/privacy throughout the WMN. Our protocol is inspired by the blind Nyberg-Rueppel digital signature scheme. In this protocol NO issues tickets to valid users only and these users can then use these tickets to access Internet or to access services provided by Internet Gateway (IGW). IGW can only verify these tickets whether tickets are valid or not but can not check “Identity of ticket holder”. This way, user anonymity has been achieved along with user authentication and data privacy throughout WMN.