Traversing Middleboxes with the Host Identity Protocol

Abstract. The limited flexibility of the Internet to support mobility has motivated many researchers to look for alternative architectures. One such effort that combines security and multihoming together is the Host Identity Protocol (HIP). HIP is a signaling protocol that adds a new protocol layer to the Internet stack between the transport and the network layer. HIP establishes IPsec associations to protect subsequent data traffic. Though the security associations are established solely between the communicating end hosts, HIP also aims to interwork with middleboxes such as NATs and firewalls. This paper investigates this interworking aspect and proposes a solution for secure middlebox traversal