Site Multihoming: Practices, Mechanisms and Perspective

Multihoming to upstream ISPs is a requirement for most IPv4 networks in today's Internet, since multihoming brings benefits such as fault tolerance, traffic engineering, and policy selection to the sites. This paper firstly summarizes the IPv4 site multihoming practices and limitations, and then surveys the current IPv6 site multihoming approaches and point out that the shim6 is the most promising multihoming solution. In addition, this paper discusses the opportunities and challenges that multihoming brings to mobility and the security issues in multihoming environment.