Eroca: A Framework for Efficiently Recovering Outsourced Ciphertexts for Autonomous Vehicles

In the near future, the next generation (5G) telecommunication network with high speed will become a reality. Autonomous vehicle system without drivers are a typical application of 5G network, for it can connect base stations, autonomous vehicles and computing centers such as traffic information clouds in a very flexible, truly mobile and powerful way. To ensure the security and privacy of autonomous vehicle system, a promise way is to encrypt the real time traffic information and upload the ciphertexts to the center cloud for easily sharing road traffic information among the vehicles. To share these real time traffic information without sacrificing privacy, attribute based encryption (ABE) and block ciphers like AES are promising tools for encrypting these large traffic information. But a basic fact for the autonomous vehicle system is that, the vehicles need to continuously update the traffic information for really catching the road’s real time traffic status, and these updates are often little compared with the status a moment ago. In this paper, we consider the problem of how to retrieve and update the data from the early encrypted file in the cloud efficiently. We propose the notion of attribute based encryption with sender recoverable (ABE-SR). Compared with ABE, ABE-SR can easily achieve message recoverable and updatable for the encrypter. We give a concrete ABE-SR scheme, discuss its features compared with the traditional ABE and prove its security. Based on ABE-SR, we propose a new framework for efficiently recovering outsourced ciphertexts for autonomous vehicles: Eroca. Finally, we give the roughly evaluation results, which show our proposal framework is practical.