Research And Design Of 4Over6 Gateway Mechanism For Internet Data Center Networks

The global IPv4 addresses have been fully assigned by the year 2011. Transition from IPv4 to IPv6 has become a key step in promoting the development of the Internet. During recent years many mainstream ISPs (Internet Service Providers) has deployed their IPv6 networks on large scale, but the vast majority of upper-layer applications and services provided by ICPs (Internet Content Providers) still support only IPv4. As for the numerous IPv4 servers deployed in IDCs (Internet Data Centers), how to ensure their accessibility by users from IPv4 Internet has become a key technical issue when promoting global IPv6 transition.In this paper I present a possible solution to this issue. Firstly, I review the requirement of IDC network for IPv6 transition solution, and survey the current mainstream IPv6 transision mechanisms. I choose Public 4over6 as the foundation of my study through comparative analysis of several different mechanisms. Then I propose a solution called 4over6 gateway solution for IPv6 transition of IDC networks. By expanding the function of both the gateway device of the IDC network and the core router of the access network, this solution enables the bi-directional accessibility between the IPv4 servers and the IPv4 Internet through the IPv6 access network in the middle.I review two issues as the most important technical challenges, including the configuration of IPv4 gateway address of IPv4 servers and the management of IPv4/IPv6 address binding states on 4over6 core router. In order to get rid of the first issue, I make an expansion of 4over6 gateway’s function, using it to automatically modify the IPv4 gateway address provided by the DHCP server through the process of DHCPv4-over-IPv6. In addition, by using a new DHCP option to carry the IPv4 address of the server and deliver this information to 4over6 core router, the 4over6 gateway can automatically configure the binding state maintained by the 4over6 core router. As such, the challenge of establishing tunnel can be resolved.According to the above study, I present the design and implementation of the 4over6 gateway prototype system. With the usage of Linux network kernel API and ISC (Internet System Consortium) DHCP open source project, I implemented both the 4over6 gateway and 4over6 core router on the Ubuntu OS, and verify the feasibility of 4over6 gateway technology solutions through functional and performance testing.