Protection of Data Dispersion in Mobile Ad-Hoc Networks

Abstract

A Mobile Ad-Hoc NETwork (MANET) is established among a group of autonomous nodes that communicate with each other using a multi-hop radio network which maintains connectivity in an infrastructure-less environment Each node is free to move independently and participates in forwarding data for other nodes Unlike wired networks there is no fixed and dedicated link available between the nodes So any node within radio range can serve as access between nodes This nature of open medium makes MANET difficult to restrict access and also it attracts malicious users who sniff or cheat other normal users In addition the dynamic and non-centralized features of MANET make it more difficult to implement security mechanisms than in traditional wired networks In this dissertation we propose three mechanisms to enhance the security of data dispersion in MANET First a (n t n) secret sharing method is applied towards a group-based mobile network architecture to provide authentication and key management services All nodes participate in key pair generation as shareholders using a threshold secret sharing scheme This group-based network consists of multi-level participants The nodes participating at different levels have different identities The node identity in a higher-level subset is different from the larger common group In the subset shared information is broadcast efficiently and securely without risk of eavesdropping from the larger group Secondly we propose a specification based intrusion detection scheme (SIDS) with the concept of two-hop integrity stamping (THIS) which utilizes previous hop routing messages to assure the integrity of the routing message The vulnerable message fields that could be tampered with during dispersion are protected by this method The proposed scheme is lightweight and deployable in a distributed and mobile environment When employing the designed idea into the AODV routing protocol experimental results demonstrate suitable performance in MANET Finally we present a Letter-based Visual Cryptography Scheme (LVCS) where pixels are replaced by letters for the share images Shares can be constructed using meaningful data as subterfuge while carrying secret data in plain sight and an adversary will not recognize them as containing secrets The secret information only can be reconstructed when the threshold condition is satisfied Otherwise eavesdropping reveals nothing even if the packet with secret shares is sniffed In addition LVCS has a novel stack-to-see property which requires neither knowledge of cryptography nor complex computations for decryption It can decrease the resource consumption of encryption and decryption Therefore we apply these three schemes to raise the security of data dispersion in MANET

Date of Award	2016 Jun 24
Original language	English
Supervisor	Hui-Tang Lin (Supervisor)