# DOSS Protocol for Data Caching and Sharing Security in a 5G Network
## 2 Related Work  
In addressing 5G security, much attention has been given to physical layer and network security, providing the UE with secure access to the network. The related work in [11; 12; 13; 14; 15; 16] explored different physical layer security techniques such as artificial noise injection to improve channel quality, anti-eavesdropping signal methods and secure beamforming to enhance the spatial distribution properties of the transmitted signal, while the related work on network security [3; 17; 18; 19; 20; 21] analyzed the 3 GPP specified protocols [1] for flaws by formally analysing the protocols' security properties and suggesting some improvements. These include enhancement of diameter protocol security, ensuring that Security Anchor Function (SEAF) should never initiate unsolicited authentication request after synchronization failure, and adding a Subscriber's Permanent Identifier (SUPI) in the message sent from Authentication Server Function (AUSF) to SEAF when confirming the session key after as successful primary authentication between the UE and HN. Different security solutions have been proposed specifically to address security at the network level, which provides the basis of the service level security. The authors in [22] discussed mobile edge computing and its security issues and proposed a multi-server protocol that providing authentication, key establishment between UEs, privacy protection, and UE tracking by the SP. In [23], the authors explored identity protection in legacy and 5G networks. They proposed an anonymous access authentication scheme, providing the users' identities protection, analyzed and verified with formal methods and BAN logic. The authors in [24] explored multi-server and small cells in heterogeneous networks. They considered authentication, key exchange, data storage, and transmissions. They analyzed the protocol in [25] that claimed to provide security in multi-server architecture in 5G but had some flaws. They improved the protocol by proposing some improvements. In [26], authors explored Wireless Sensors Networks (WSN) and IoT in 5G. Base on the work in [27] that provided authentication and access control scheme, they introduced a system architecture that integrated IoT with 5G and proposed a formally analyzed ECC-based security solution providing authentication, authorization, key agreement, and privacy-preservation for WSN in 5G. Most of the related work on service security discussed caching schemes and storage techniques, not much on the service security mechanisms. The authors in [28] proposed cooperative edge caching architecture for caching and computing resources at the wireless network edge in 5G. In [29], the authors proposed a caching and sharing optimization solution to assist sensor networks in 5G for content delivery to the UE. Enabling ICN with edge computing improves communication and content distribution, the authors in [30] proposed an ICN-capable Radio Access Network (RAN) architecture for edge computing in 5G that offers caching at the edge. Also, [31] discusses CCN-based caching in 5G and proposes an edge caching scheme based on content-centric networking. On service security in 5G, the authors in [32] discussed malicious access and destruction of data and proposed a label-based access control mechanism that provides authentication to authorized nodes to ensure authenticity and integrity of data using embedded labels, while [33] proposed a security mechanism that uses hash function technique to protect data sharing in for 5G networks. In [34], the author proposed an authentication and access control mechanism for 5G applications that can be delegated to the 3 rd parties SPs at the edge, providing security at the network and service level. The authors in [4] proposed a federated authentication and authorization protocol that provides secure access to services from multiple SPs and single sign-on to users using federated identity for seamless access to services in 5G.