Multi-access edge computing (MEC) has been regarded as a promising technique for enhancing computation capabilities for wireless networks. In this paper, we study physical layer security in an MEC system where multiple users offload partial of their computation tasks to a base station simultaneously based on non-orthogonal multiple access (NOMA), in the presence of a malicious eavesdropper. Secrecy outage probability is adopted to measure the security performance of the computation offloading against eavesdropping attacks. We aim to minimize the sum energy consumption of all the users, subject to constraints in terms of the secrecy offloading rate, the secrecy outage probability, and the decoding order of NOMA. Although the original optimization problem is non-convex and challenging to solve, we put forward an efficient algorithm based on sequential convex approximation and penalty dual decomposition. Numerical results are eventually provided to validate the convergence of the proposed algorithm and its superior energy efficiency with secrecy requirements.

翻译：多存取边缘计算(MEC)被认为是提高无线网络计算能力的一个很有希望的技术。在本文中,我们研究了MEC系统中的物理层安全性,在这个系统中,在恶意窃听器面前,多个用户在非横向多重访问的基础上,同时将其部分计算任务卸到基地站(NOMA),恶意窃听器在场。采用了隐蔽性溢出概率,以衡量对窃听攻击进行卸载的计算的安全性能。我们的目标是尽量减少所有用户的总能源消耗量,但受保密卸载率、保密溢出概率和NOMA解码顺序的限制。虽然最初的优化问题是非电解密性且难以解决的,但我们还是根据相近率提出了高效的算法,并惩罚双重解剖。最终提供了数值结果,以证实拟议的算法及其高能效与保密要求的趋同。