Efficient certification path discovery for MANET

A Mobile Ad Hoc Network (MANET) is characterized by the lack of any infrastructure, absence of any kind of centralized administration, frequent mobility of nodes, network partitioning, and wireless connections. These properties make traditional wireline security solutions not straightforwardly applicable in MANETs, and of course, constitute the establishment of a Public Key Infrastructure (PKI) in such networks a cumbersome task. After surveying related work, we propose a novel public key management scheme using the well-known web-of-trust or trust graph model. Our scheme is based on a binary tree formation of the network's nodes. The binary tree structure is proved very effective for building certificate chains between communicating nodes that are multihops away and the cumbersome problem of certificate chain discovery is avoided. We compare our scheme with related work and show that it presents several advantages, especially when a fair balancing between security and performance is desirable. Simulations of the proposed scheme under different scenarios demonstrate that it is effective in terms of tree formation, join and leave occurrences, and certificate chain establishment.