Extending REBEKAH-IP with central port allocations for un-ambiguous IPv4 address expansion

addresses has attracted the attention of both the research community and the industry. The problem becomes even more pressing with the introduction of third generation (3G) cellular networks which are predicted to introduce hundred of millions of new IP capable terminals over the next few years. The cellular industry has decided to combat this problem by using IPv6 for the new terminals, but unfortunately since the vast majority of services will reside in the IPv4 address space the problem will remain for the foreseeable future. There have been many proposals on how to address the issue by extending the IPv4 address space so that the introduction of IPv6 is given more time for a smooth transition. One of these proposals, REBEKAH-IP is promising in that it is scalable and does not limit the services that can be supported. However, the scheme is limited in that there is a possibility for call blocking as the system gets loaded. In this paper, we introduce an improvement to REBEKAH-IP in which this side effect is removed, creating a robust and fully scalable system. I. INTRODUCTION ne of the most pressing issues in the Internet today is the shortage of IPv4 addresses. The header format of IPv4 has a fixed size of 32 bit for addresses and due to this limitation it is predicted that all addresses will be occupied by year 2008 [1]. In order to combat this situation, the IETF has decided to introduce the next generation of IP, version 6 [2]. However, even though there are mechanisms in place for the transition to the new protocol [3], the process is very slow due to increased complexity to the individual networks as well as the lack of financial incentives for the migration. This has resulted in an almost non-existent IPv6 deployment in the Internet today. The cellular industry has identified this problem and therefore specified IPv6 as the primary network protocol in the third generation cellular networks. The incentive is the