The Research Of Connection Approach Between Hosts That Are Located Behind NATs

IP address (Internet Protocol address) is the base of the network, the research of China Internet Network Information Center (CNNIC) shows that there only ten hundred million IPv4 addresses are available. It seems large, but will soon be exhausted since the Internet is growing at such a high speed. IP version 6 is the best method of extending the IP addresses, but it will take years before the existing network infrastructure migrates to the new protocol because it requires modification of the entire infrastructure of the Internet.Network Address Translation (NAT) is a prevalent method of connecting multiple computers to the Internet by translating the private addresses into legal addresses. It enables private IP inter-networks that use non-registered IP addresses to connect to the Internet. Most of home users and small businesses use this method to connect their network to the Internet. NATs only allow connections originating from within the internal network and drop unsolicited connection attempts, since they have no way of knowing to which internal host the packet should be forwarded to. Peer-to-Peer (P2P) networks can not work since each NAT only allows the establishment of outgoing connections. The P2P networks have become increasingly popular,how to traversal through NATs is very important.There are several methods of traversaling through NATs, including Full Proxy,STUN,TRUN and so on. This paper analyzes the character of these methods and presents a novel mechanism to create connections between two hosts behind NATs. We use the distributed person computers which have the globally unique IP address to replace the server, which can resolve the problem of server bottleneck. We also present another novel mechanism to find the best agent what can improve the agent's efficiency. The new traversal method in this paper will give some advantages to the existing solutions and the Next Generation Network.