Over the past decade, huge progress has been made in the development of Autonomous Vehicles (AVs), also known as self-driving or driverless cars. But it is still too early to sit back and nap - you can take your hands off the wheel but you still need to have your eyes on the road. The AVs currently out on the roads are only partially automated, meaning they require human oversight to work safely.  
As most of the communication on AV networks take place through wireless communication links, there is an inherent risk of the technology being hacked for malicious purposes. This is why securing the network is key for AVs to deliver on their promise of being safer than traditional cars. Compromised security can cause casualties which may have fatal outcomes. Ali Hussain Khan, Dr Naveed Ul Hassan and Dr Zartash Afzal Uzmi from the Department of Electrical Engineering at LUMS, and Dr Chuadhry Mujeeb Ahmed from University of Strathclyde have published a research article to address the security issues associated with this vulnerable technology. The research proposes and tests an authentication framework based on blockchain technology, termed Proof-of-Communication-Capability (PoCC), which acts as a defence mechanism in wireless networks against malicious actors pretending to be valid communication devices. This type of hacking attack is also known as communication capability spoofing. 
Blockchain, a technology popularized for crypto-currencies, can be utilized effectively for wireless communication between AVs. Blockchain works by replicating the data at multiple computer nodes, thereby making a network more secure and less prone to failures. However, blockchain’s strength can also be its weakness. Blockchain inherently relies on consensus – informally speaking, consensus can be defined as an agreement between a set of computers which communicate over a network. If this consensus is subverted or delayed, nodes in a blockchain slow down which can be catastrophic for AVs. Hussain Khan and his fellow researchers identified four different types of attacks that are capable of downgrading the system.

These nodes can either (1) falsely report superior communication capabilities; (2) turn malicious after joining the network and start reporting upgraded wireless communication; (3) report downgraded wireless communication capabilities while joining the network; or (4) turn malicious after joining the network and start reporting degraded wireless communication capabilities. 

PoCC authentication framework helps detect these malicious nodes by providing a set of consensus rules, a form of test to ensure that only non-malicious nodes join the network. For instance, the claimed capabilities of nodes can be tested through physical features like location and propagation time (the time it takes to transmit data) before joining the network to prevent type (1) malicious nodes to enter. PoCC authentication framework comprises of consensus rules that have been developed in relation to every possible malicious node to prevent them from sabotaging the blockchain. After testing the framework in different scenarios where nodes turn malicious, the researchers concluded that the PoCC authentication framework is not only capable of detecting malicious nodes, but the physical attributes of the consensus rules make it difficult to trick the system. Implementation of the proposed framework in AVs could contribute in avoiding causalities on the road without human intervention and thereby push AVs one step closer to widespread adoption.