In many scenarios, Internet connectivity may not be available. In such situations, device-to-device (D2D) communication may be utilized to establish a peer-to-peer (P2P) network among mobile users in the vicinity. However, this raises a fundamental question as is how to ensure secure communication in such an infrastructure-less network. In this paper, we present an approach that enables connectivity between mobile devices in the vicinity and supports secure communication between users in Internet-isolated locations. Specifically, the proposed solution uses Wi-Fi Aware for establishing a P2P network and the mTLS (mutual Transport Layer Security) protocol to provide mutually authenticated and encrypted message transfer. Besides, a novel decentralized peer authentication (DPA) scheme compatible with Wi-Fi Aware and TLS is proposed, which enables peers to verify other peers to join the network. A proof-of-concept instant messaging application has been developed to test the proposed DPA scheme and to evaluate the performance of the proposed overall approach. Experimental results, which validate the proposed solution, are presented with findings and limitations discussed.

2022 Seventh International Conference On Mobile And Secure Services (MobiSecServ)