Abstract
The key exchange Diffie-Hellman protocol originally works over the group Z*p where p is at least a 300-digit number. Even though this implementation is simple and secure, it makes the protocol unsuitable for devices with limited computational power.
This fact led to a research of other algebraic structures which could be used as a platform for this protocol in order to decrease the computational and storage costs. Such attempt can be found in the work of D.
Kahrobaei et al. posted in 2013. D.
Kahrobaei et al. proposed a structure of small matrices over a group ring as a platform and claimed that this modification will not affect the security of the Diffie-Hellman protocol. We will attack this modification and prove that it is not secure with the help of the theory of symmetric group representations.