5G-assisted Device to Device (D2D) communication can be broadly categorized into three use case scenarios: In Coverage, Relay Coverage, and Out-of Coverage. The main challenge lies in ensuring secure communication in Out-of Coverage scenarios, as in this situation, neither of the two devices is within the 5G network’s coverage area. Although several researchers have developed authentication mechanisms for securing D2D communication, most are unsuitable for Out-of Coverage scenarios. Additionally, many of these mechanisms cannot withstand free-riding attacks due to the absence of a trusted entity. In a 5G cellular network, a trust relationship can be established between a registered device and the home network through mutual authentication whenever the former is within the latter’s coverage area. Leveraging this trust, this paper proposes a lightweight 5G-assisted authentication protocol for mutual authentication between two communicating devices in Out-of Coverage scenarios. The proposed protocol meets the necessary security goals and mitigates various security attacks, including free-riding attacks. The correctness of the proposed protocol is formally established using the Scyther tool and Random Oracle Model. Furthermore, performance analysis shows that the protocol is efficient in terms of computation overhead, communication overhead and energy consumption compared to similar works in the literature. The computation overhead is found to be 596.12 ms for the Requestor device and 587.26 ms for the Requestee device. The communication overhead is 2720 bits and the total energy consumption for both devices combined is found to be 3016.93 millijoules.

中文翻译：

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一种 AKA 协议，用于 Out-of-Coverage 场景中的 5G 辅助 D2D 通信


5G 辅助设备到设备 （D2D） 通信大致可分为三种用例场景：覆盖范围内、中继覆盖和覆盖范围外。主要挑战在于确保在覆盖外场景中进行安全通信，因为在这种情况下，两台设备都不在 5G 网络的覆盖区域内。尽管一些研究人员已经开发了用于保护 D2D 通信的身份验证机制，但大多数机制都不适用于 Out of Coverage 场景。此外，由于缺乏受信任的实体，其中许多机制无法承受搭便车攻击。在 5G 蜂窝网络中，只要注册设备和家庭网络位于后者的覆盖区域内，就可以通过相互身份验证在注册设备和家庭网络之间建立信任关系。利用这种信任，本文提出了一种轻量级的 5G 辅助身份验证协议，用于在超出覆盖场景下两个通信设备之间进行相互身份验证。提议的协议满足必要的安全目标并缓解各种安全攻击，包括搭便车攻击。使用 Scyther 工具和 Random Oracle 模型正式确定所提议协议的正确性。此外，性能分析表明，与文献中的类似工作相比，该协议在计算开销、通信开销和能耗方面是有效的。发现请求者设备的计算开销为 596.12 毫秒，被请求者设备的计算开销为 587.26 毫秒。通信开销为 2720 位，两种设备的总能耗加起来为 3016.93 毫焦耳。