A Study on authentication scheme for channel assignment mechanism in multi - radio multi - channel wireless mesh networks

Hyancinth is one of the popular node architectures proposed by Ashish et al. for efficient channel assignment in multi-radio multi-channel(MRMC) wireless mesh network(WMN). However, we found out that Hyacinth was designed without considering the security mechanism. A fake channel control packet from an external attacker can degrade the network goodput. Also, an internal attacker e.g., compromised node, can launch denial of service(DoS) attacks by two methods: malicious channel switching(MCS), and consecutive channel switching(CCS) attack. In this thesis, we propose an authenticated channel assignment mechanism for MRMC WMN, and provide secure channel control, and message verification module to prevent the known attacks. First, we provide secure channel control to protect the channel assignment process from an external attacker. We use cryptographic primitive e.g., a block cipher to encrypt the channel control message. Second, we add additional module called, Message verification module, which consists of three phase, Channel status gathering, Discrepancy checking and Message verification. In channel status gathering, one node collects the channel status of other nodes within the interference range, and selects the candidate preferred channel. In discrepancy checking phase, each node within the interference range checks the discrepancy of current channel and interface from the requested channel and interface. In message verification phase, each node compares the number of the requested channel from the PARENT node with his candidate preferred channel to verify whether the change request is legitimate or not. Our simulation result using NS-2 simulator shows that proposed scheme can protect channel assignment process from both external and internal attacker in the presence of the attacker that launches MCS and CCS attacks together.