This document proposes security extensions that are applicable to P2PSIP overlays that follow the base protocol described in the WG leading drafts. The proposed extensions exploit symmetric/asymmetric cryptography and a key refresh mechanism to protect the signaling exchanged between the participating peers in order to enhance the robustness of the system against several types of attacks that are common to peer-to-peer networks. The refresh mechanism is either supervised by higher-level trusted peers or exclusively controlled by the members of the overlay.