Research Of Ipv4 Address Resources Configuration Mechanisms Based On Ipv6 Access Network

With IPv4 addresses running out, the Internet is transitioning to IPv6 worldwide. However, transition to IPv6 cannot be completed in a short period of time because IPv4 is widely used and is supporting various services. So IPv4 and IPv6 will coexist for a long time. In order to provide continuous IPv4 services and promote IPv6 deployment during the IPv6 transition period, operators have to allocate IPv4 address across IPv6-only networks. Because of the variety of network architectures, different operators have different requirements for IPv6 transition. The Internet Engineering Task Force (IETF) has proposed many solutions to this issue, but there is not a "one-fits-all " solution.This paper aims at solving the issue of configuring IPv4 across IPv6-only networks. Firstly, it analyzes the IPv4-over-IPv6 transition architecture, and summarizes the requirements for configuring IPv4 over IPv6 at different levels. Then, it surveys the proposals in IETF according to the core principles and gives a brief comparison.Based on the survey, this paper proposes the DHCPv4 over DHCPv6 mechanism, focusing on the dynamic allocation of IPv4 and the configuration of other IPv4 parameters. The mechanism combines the functionality of DHCPv4 and DHCPv6 by transporting DHCPv4 packets with DHCPv6. It preserves the features of DHCPv4 and is compatible to the structure of DHCPv6, without affecting the future development of DHCPv6. This paper also proposes the "DHCPv4 Port Set Option" mechanism. This mechanism takes IPv4 address and port set as the identifier for a client. It uses DHCPv4 option for conveying information and combines with DHCPv4 over DHCPv6, which provides management of the shared IPv4 address in the IPv6 transition scenario.Some of the mechanisms proposed in this paper have been standardized in IETF, and have received supports from operators and vendors.