Stealth: A Heterogeneous Covert Access Channel for Mix-net

The anonymous communication network based on the Mix-net model can protect the communication privacy by hiding the communication relationship between users. However, most anonymous communication networks lack the entry hiding mechanism for Mix-net. This paper proposes an anonymous network ingress protection mechanism, which provides a covert data transmission channel between end users and Mix-net nodes based on various Internet public services. In this paper, a covert transmission channel is implemented in the Internet environment based on three heterogeneous protocols, WebDav, Git, and SMTP. The experimental results show that this method can meet the performance requirements of data transmission while maintaining high privacy.