Use Private Ip Addresses. Softswitch

As a result of Ipv4 address space limitation, in order to save the address space, widely has the NAT address translation in the current IP network. Take the city territory net as the example, the NAT/Firewall technology is usually used in such as the enterprise selvage, plot selvage, city territory selvage. In order to cause Voip to apply generally is suitable for these network situations, must solve Voip to pass through these NAT/Firewall equipment the question.First this article introduced at present domestic and foreign studies needs to solve this kind of problem, current attention focal point and future prospect forecast. Introduced the soft exchange system structure and the basic function; And the IP address plan obtained from the soft exchange network, analyze the questions for media streams and the signaling streams on two stratification planes the Voip equipment to pass through the firewall, and proposed the use application level NAT solution and the technical realization principle; And specifically explained the soft exchange network IP network planning principle and the method, and unify two concrete projects cases to show this plan the feasibility.