PHYve-G: Evaluating Channel Reciprocity and Secret Key Generation in 5G Networks

Abstract:
Data privacy is often thought of as a topic above OSI Layer 3 with custom security protocols such as Transport Layer Security (TLS) or Internet Protocol Security (IPsec). These protocols, however, are only additions to existing standards, increasing the security patchwork structure of communication networks. These concepts neglect the significant security opportunities originating from the physical layer, creating the basis for any communication network. This layer is particularly unique when envisioning wireless media like 5G mobile networks. Therefore, our paper creates the fundamental baseline for secret key generation on the physical layer in 5G networks by proposing a channel quantization scheme that can be executed on readily available hardware. Additionally, we propose the necessary means to create shared cryptographic material, based on the resulting channel reciprocity of the 5G network. The evaluation of this scheme shows that it is capable of generating high-entropy keys, depending on the quality of the channel quantization. With the results of this paper at hand, future concepts to include lightweight security in 5G networks can be created.