Recently, as non-face-to-face culture has spread in modern society due to the COVID-19 pandemic, the demand for video conference platforms has been rapidly increased. Although the video conference platforms provide various advantages in terms of scalability and convenience, there are several issues for the security and privacy of participants to be solved. Furthermore, since the video conference can be available in a resource-constrained smart device, the performance problem including the degradation of image and sound can be caused. Therefore, for a secure and efficient video conference, user authentication and group key agreement scheme are essential.
In 2020, Luo et al. proposed a secure mutual authentication and group key agreement scheme for video conference systems. However, Luo et al.''s scheme cannot prevent a known temporary key and key compromise impersonation attack. Thus, this thesis propose a secure and efficient user authentication and group key agreement scheme in video conference systems using elliptic curve cryptography while resolving the security vulnerabilities of Luo et al.''s scheme. This thesis demonstrated that the proposed scheme can prevent various security attacks and also ensure anonymity and scalability by performing informal security analysis. Moreover, this thesis proved the security of the proposed scheme by using formal security analyses, such as the BAN logic and AVISPA. This thesis then demonstrated that the proposed scheme offers more efficient computation and communication costs compared with related schemes by comparing the performance analysis. Consequently, the proposed scheme is suitable for a practical video conference systems and also is expected to provide secure and efficient services.