With the rapid advancement of information technology, traditional centralized cloud computing systems face challenges in meeting the stringent low-latency demands of emerging applications. To tackle this issue, this paper proposes a delay-aware cloud-edge architecture that incorporates the distributed characteristics of edge infrastructure, enabling low latency collaboration among edge nodes within the same geographic region. Furthermore, based on this architecture, a dynamic data replica management scheme is introduced, involving synergistic mechanisms between edge nodes and cloud centers to optimally place data replicas on the most suitable edge nodes. The scheme adopts a hierarchical strategy: edge nodes perform short-term localized management of data replicas, while the cloud executes long-term holistic oversight. Experimental results demonstrate that the dynamic approach effectively reduces user access latency, minimizes replica migration frequency, and decreases network bandwidth consumption.

After analyzing the long-term evolution (LTE) authentication and key agreement process (EPS-AKA), its existing security vulnerabilities are pointed out. Based on elliptic curve cryptography (ECC) self-certified public keys, this paper proposes an ECC self-certified authentication key agreement scheme (ESC-AKA). This scheme includes the addition of a trusted center (TC), which generates the public keys for the home subscriber server (HSS), the mobility management entity (MME), and the user equipment (UE). Three communication protocols are designed, including MME/HSS registration, UE registration, and UE access. A strand space model is used to carry out the formal analysis, and performance and security analyses are carried out. The results show that this scheme can compensate for the security vulnerabilities of the original EPS-AKA scheme. It implements the encrypted transmission of the international mobile subscriber identity (IMSI), and realizes the mutual authentication between the HSS and MME, the MME and UE, and the HSS and UE. Because the self-certified public key cryptosystem is adopted in this scheme, communication encryption is ensured, and the risk of the TC simultaneously mastering the public and private keys is avoided. This scheme is proven to be effective in protecting the communication security of the LTE network.