According to the problem in the transitional period of IPv4/ IPv6 and the shortages of the mainly techniques during this period,this paper proposed the IPv6 tunnel technology based on multi-core,designed its model,used the multi-core flow technology,the lock-technique and the multi-core load-share model to speed up transmitting,protected the critical resources and improved the whole performance.

The application of IPv6 tunneling technology based on NAT was analyzed,some defects were proposed;Improving technology for IPv6 tunnel was proposed that base on Client-server model tunnel and the properties state of the server,fixed IPv6 address for NAT user can be distributed,symmetric NAT user can be supported and security was increased.

Through an in-depth study of Netfilter mechanism and IPv6 tunnel technology, an implement of a DiffServ application gateway by using netfilter mechanism under.

The paper gives a brief introduction to the principle of the IPv4/IPv6 tunnel technology, provides a detailed method of realizing IPv4/IPv6 tunnel technology, which has been verified and applied.

IPv6-in-IPv4 tunnel discovery technology is researched in the paper,and a set of IPv6-in-IPv4 tunnel discovery technology based on initiative detection is provided.