Security among UPFs belonging to Different 5G/B5G/6G Networks

Recently, 5G/B5G/6G networks (5G for short) have been gloriously developed to give us colorful lives and make our daily activities more convenient than before. On the other hand, online meetings, like video conferences and online educations, have been popularly held everywhere in the world. Nevertheless, in such a meeting on 5G networks, a packet P transmitted from a User Plane Function (UPF), e.g., UPF1 of a 5G, e.g., 5G(1), to P's destinations, e.g., the set {UPF2, UPF3, . . .UPFn}, respectively, in {5G(2), 5G(3), . . .5G(n)}, is not secure, even not encrypted, particularly when P goes through the Internet. Hackers may duplicate P, i.e., data leakage on the connections among these UPFs. The situation needs to be avoided when data of the meetings ought not to be leaked, e.g., for an important military conference. Therefore, in this study, we propose a security architecture, named Group Key using IKA (GKIKA), which encrypts/decrypt packets before sending them, e.g., EC1 in 5G(1) encrypts P and then sends P's ciphertext which will be decrypted by edge computers {EC2, EC3, . . .ECn} where ECj is in 5G(j), 2 <= j <= n. Our security scenarios include data transmission among n-parties, n >= 2. When n = 2, symmetric or asymmetric cryptography is adopted depending on the security level and time constraints required. As n > 2, the Initial Key Agreement (IKA) is utilized to establish a secret key for all participating ECs. Other security mechanisms, like message authentication code and time stamp, are also utilized to enhance the security level of data transmission. Our analyses show that the GKIKA can effectively avoid some types of attacks.