HIP for Linux (HIPL) is a project organized by Helsinki Institute for Information Technology (HIIT) and Helsinki University of Technology (HUT) in collaboration with Distributed Systems Group at RWTH Aachen. The project has developed an open source implementation of Host Identity Protocol (HIP) and many of its extensions. The web pages are located at infrahip.hiit.fi. The hipl-users mailing list is for HIPL related open discussion.