A Distributed Waypoint Service Approach to Connect Heterogeneous Internet Address Spaces

The rapid growth of the Internet has made IPv4 addresses a scarce resource. Today we witness two major trends to get around this problem. The first is to upgrade and deploy networks using IPv6; the second is to deploy networks using reusable-IPv4 addresses. As a result, the Internet is rapidly evolving into a collection of networks of heterogeneous address spaces. Such development jeopardizes the universal connectivity property of the Internet. In this paper, we address the fundamental problem of providing connectivity in the address-space heterogeneous Internet. The main difficulty is that, without IPv4 addresses, IPv6 or reusable-IPv4 hosts simply cannot be reached by IPv4 hosts. To solve this problem, we propose a distributed waypoint service called AVES. The key idea is to use IPv4 waypoints (3rd-party network agents) as relays to connect any IPv4 host to an arbitrary set of IPv6 or reusable-IPv4 hosts. As a result, the internetworking heterogeneity is handled by the waypoints and hidden from the existing IPv4 infrastructure, making non-intrusive deployment of AVES possible. Once AVES is deployed, the service is instantaneously accessible transparently by any IPv4 host in the Internet via host name resolution. This approach is unique because it solves the connectivity problem without changing the networking layer of existing systems. We have implemented AVES using FreeBSD and Linux.