Authentication Protocol for Enhanced Security of the Automatic Identification System
Robert E. Litts, Dimitrie C. Popescu, Otilia Popescu · 2021
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 by malicious parties. In this paper we present an authentication protocol that enhances the security of the AIS by providing it with a message integrity and broadcast authentication feature. The proposed protocol uses time-delayed key disclosures of hash chains as part of a message authentication code appended to packets to verify the authenticity of a user and requires only one additional time slot for broadcast authentication compared to the existing standard. This is significant reduction in message overhead requirements compared to alternative approaches that use public key infrastructure (PKI). A test implementation of the proposed protocol indicate that it can be deployed as a link layer software update to existing AIS transceivers and can be deployed within the existing AIS technical standards as an expanded message set.