Layered Switching Network (1)

1. Challenges Facing the Internet

Internet is one of the most influential scientific and technological inventions in the 20th century to human society. It provides a new means of communication, information exchange and information acquisition, greatly accelerating the process of information technology in society. At present, more than 3 billion people around the world are using the Internet, and more than 3/4 of the population of large countries such as China and India are not surfing the Internet. The reason why the Internet is developing rapidly is that it conforms to the needs of the society for the advancement of information technology, and adopts a concise and clear Packet Exchange Protocol and flexible routing methods.

Compared with the previous circuit switching technology, packet switching technology requires complete routing technology. Using computer intelligence, information is exchanged regularly between routers to form a route table. Each vro can view its own route table based on the destination address written on the outer packet, and then send the data packet to the destination on a one-stop basis. No manual intervention is required for all these forwarding tasks, including route table updates, which are automatically completed by the router. With the ability of routers to automatically adapt to the network structure, people can easily establish a network structure with any connection when they want to connect to the network. When the reliability of network components, especially communication lines, is low, the method of automatically finding routes between the network structure of any connection and the router is very effective. The routing technology is the core and soul of the Internet. No one can deny this.

It can be said that in the early stages of network development, the advantages of the Internet over other network systems were the simplicity of network protocols, packet switching and routing technologies. However, with the development of technology and the emergence of advanced applications, especially when the network scale exceeds the imagination of early network designers, these advantages of Internet have encountered unprecedented challenges, some are no longer advantages, and some will turn into factors that impede the continued development of the Internet.

When the network scale continues to grow and the demand for real-time communication increases, the Internet has encountered a series of difficulties: the network scale makes the route table huge, and the router cannot forward data packets quickly and effectively; local Network behavior, such as network topology changes, channel or equipment faults and recovery, and network management personnel configuration and operation errors, all routing information must be reported and changed to the world as a global action, so that the backbone network router is overwhelmed. After a network event occurs, the route information convergence time reaches minutes, A large number of data packets oscillate or circle in the network; routers become more complex, and costs and power consumption are getting higher and higher. To overcome the disadvantages of packet switching technology and obtain the benefits of circuit switching, we need to increase the virtual circuit switching technology, network protocols become more and more complex. The high reliability of optical communication lines makes the network structure of any connection no longer advantageous. Because it is difficult to manually determine the exact route of data packets in the network channel, network designers cannot precisely allocate suitable bandwidth for each channel, and it is difficult to make full and reasonable use of network channel resources; slow end-to-end error recovery means, lack of Network Self-healing capabilities, making it difficult for the Internet to provide telecom-level service quality; The uncertainty of network behavior makes it difficult to effectively manage and control the network. There is no strict distinction between the network address space and the user address space, and the backbone network signaling is fully integrated with the user network signaling, this poses a critical security threat to the backbone network equipment. The forgery of the source network address makes it difficult to effectively investigate and suppress bad network behavior. All these difficulties are fatal. In addition, the early estimation of the Internet development scale is insufficient, and the IPv4 address space will be exhausted within one or two years. Currently, a large number of private addresses will impede the end-to-end communication capability. The IPv6 protocol with a large address space is used. If the network hierarchy is not taken into account, the route table will increase dramatically, and the complexity of the router and its "bottleneck" position in the network will become more and more serious. At present, a large number of improvement measures are difficult to solve the problem, which suddenly increases the complexity of network protocols. The Internet must undergo major reforms.

This article introduces a new network architecture: layered switching network technology to address a series of challenges that cannot be addressed by the Internet. Using this technology, the router is completely lost, and the network regression is concise. The data packet path can be predicted and network channel resources can be reasonably used; localized events such as changes in network topology information, failure and recovery of network devices and communication lines, and misoperations of network administrators; make the fast self-healing capability independent from another complex network (such as SDH/SONET), make the multicast tree naturally formed, and separate the backbone network address space from the user address space; it is easy to track users' bad behaviors.

Any reform on the Internet or the use of a new technology on the Internet must be fully compatible with the original Internet protocols. Otherwise, it will not work.