Research Article A Novel Variable Pseudonym Scheme for Preserving Privacy User Location in 5G Networks Mamoon M. Saeed , 1 Rashid A. Saeed , 2 Rania A. Mokhtar , 2 Hesham Alhumyani , 2 and Elmustafa Sayed Ali 3 1 Communications and Electronics Engineering Department, Faculty of Engineering, University of Modern Sciences, Sanaa, Yemen 2 Department of Computer Engineering, College of Computers and Information Technology, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia 3 Department of Electrical and Electronics Engineering, Faculty of Engineering, Red Sea University, Port Sudan, Sudan Correspondence should be addressed to Elmustafa Sayed Ali; elmustafasayed@gmail.com Received 8 January 2022; Revised 28 January 2022; Accepted 25 February 2022; Published 30 March 2022 Academic Editor: Muhammad Arif Copyright © 2022 Mamoon M. Saeed et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Due to the development in 5G mobile communications, user privacy becomes the main challenge, especially with the multiplicity of services and applications that can be accessed. Location privacy is related to the user privacy in terms of the possibility of tracking and unwanted advertisements, as well as the possibility of exposure to suspicious activities and terrorist attacks based on the user location. Accordingly, previous mobile systems use pseudonyms instead of a permanent identity to preserving the user’s location privacy in mobile networks, by what is known as the Cellular Radio Network Temporary Identifiers (C-RNTIs). e C-RNTI protects the user privacy relatively, but it faces some problems due to the clear text of the user in CRNI exchange, which will make the user easily trackable by man-in-the-middle attack. is article aims at proposing a new algorithm that improves the user’s location privacy and enhances the capabilities of the 5G infrastructure in terms of confidentiality and privacy. e idea is based on the use of a novel variable pseudonym (V-RNTI) algorithm that acts as a radio channel identifier for the user, which improves the allocation of pseudonyms to identify users. e proposed algorithm uses different V-RNTI values by the UE and can be changed frequently to improve the pseudonym allocation procedure. is approach can be implemented in 3GPP standard architecture by upgrading UEs and eNB by minor modifications. During this study, the proposed 5G V-RNTI authentication protocol model was built. And then, the automated analysis of the protocol model is performed by using ProVerif Model Checker. e results showed that the model works well without any noticeable problems. 1. Introduction Because of the advantages of 5G networks such as high data rate, low latency, high capacity, and wide coverage, it has rapidly grown to become the main core network [1]. e 5G network requires an enhancement in security and privacy to ensure transferring information in a safe manner. As user privacy is the main issue in 5G networks, the location privacy is considered much more important for user privacy [2]. Recognizing the characteristics of certain services for consumers in 5G technology requires the provision of secure network services. e privacy requirements of the 5G net- work may change according to the services provided by the network [3]. Meanwhile, service-oriented privacy require- ments can be enabled by 5G technology. In some 5G ap- plications, for example, in the healthcare Internet, a higher degree of privacy will be required to secure users’ infor- mation. Furthermore, a higher level of privacy protection and site privacy protection may be required [3, 4]. And a lower degree of privacy may be required in other applica- tions, such as searching for some type of location information. Hindawi Security and Communication Networks Volume 2022, Article ID 7487600, 11 pages https://doi.org/10.1155/2022/7487600