Routing security challenges significantly impact the wide-scale adoption of mobile ad hoc networks (MANET), with wormholes constituting an especially severe threat. Wormhole detection algorithms like traversal time and hop count analysis (TTHCA) and modified transmission time-based mechanism (M-TTM) combine effective detection with low traffic overheads. TTHCA measures packet traversal time (PTT) per route hop count (HC), while M-TTM compares an expected round trip time (RTT) with a measured RTT. However, using only fixed thresholds for the permissible PTT/HC and measured RTT deviations respectively, both algorithms are compromised so participation mode (PM), out-of-band (O-B) wormholes are inadequately detected in MANETs with large radio range fluctuations. This paper presents an extended variant of the TTHCA algorithm called traversal time per hop analysis (TTpHA) that dynamically adapts the PTT per hop threshold to both different node radio coverages and prevailing MANET conditions. Experimental results confirm TTpHA provides superior PM O-B detection performance compared to TTHCA and M-TTM, with commensurately low false positive rates and traffic overheads.
['Jonny Karlsson', 'Göran Pulkkis', 'Laurence S. Dooley']
A packet traversal time per hop based adaptive wormhole detection algorithm for MANETs