gPHI: Lightweight Anonymity Protocol for Anonymity at Host and AS Levels

Lightweight anonymity protocols are expected to provide anonymity service at the networking layer. Among them, PHI and its successor dPHI are promising due to the fact that anonymous path selection according to IP routing enables easy deployment at the Internet infrastructure. However, the path selection based on IP routing incurs vulnerabilities against attacks which leverage underlying Internet topology information. This paper discovers such new attacks against PHI/dPHI and designs gPHI to mitigate such attacks by extending dPHI.