Date of Award
Master of Science (MS)
Dimitrie C. Popescu
The Automatic Identification System (AIS) is used aboard the vast majority of sea-going vessels in the world as a collision avoidance tool. Currently, the AIS operates without any security features, which make it vulnerable to exploits such as spoofing, hijacking, and replay attacks by malicious parties. This paper examines the work that has been done so far to improve AIS security, as well as the approaches taken on similar problems in the aircraft and vehicular mobile ad-hoc network (MANET) industries. The first major contribution of this paper is the implementation of a Software Defined Radio (SDR) AIS transmitter and receiver which can be used to conduct vulnerability analysis and test the implementation of new security features. The second contribution is the design of a novel authentication protocol which overcomes the existing vulnerabilities in the AIS system. The proposed protocol uses time-delayed hash-chain key disclosures as part of a message authentication code (MAC) appended to automatic position reports to verify the authenticity of a user. This method requires only one additional time slot for broadcast authentication compared to the existing standard and is a significant reduction in message overhead requirements compared to alternative approaches that solely rely on public key infrastructure (PKI). Additionally, there is an embedded time stamp, a feature lacking in the existing system, which makes this protocol resistant to replay attacks. A test implementation of the proposed protocol indicates that it can be deployed as a link layer software update to existing AIS transceivers and can be deployed within the current AIS technical standards as an expanded message set.
Litts, Robert E..
"Security Improvements for the Automatic Identification System"
(2021). Master of Science (MS), Thesis, Electrical/Computer Engineering, Old Dominion University, DOI: 10.25777/zjmc-3w82