Operation-level router development history and main features

There are still many things worth learning about Operation-level routers. Here we mainly introduce the development process and main features of operation-level routers. Traditional Telecom networks will provide IP-based next-generation network evolution that integrates multiple services. Routers, as a basic component of an IP network, directly determine the capability of an IP network to provide services and are the core component of the next-generation network.

Based on the application scope, routers can be divided into enterprise-level routers and operation-level routers. An enterprise-level router is used to connect multiple local networks and enterprise networks in an enterprise to the Internet. The task is simple, and the main task is to forward packets, the requirements for security, reliability, forwarding performance, and service generation capabilities are not very high. As the basic component of a new generation of telecom networks, operation-level routers must meet the strict requirements of telecom services. This is the key and difficulty for the continuous development of router technologies and products. This article describes the capabilities and product features of the routers currently operating on telecommunication networks.

I. Development History of operation-level Routers

A router is a device that connects networks at the IP layer. The IP packet is sent from the source host and enters the connected router. The router searches the route table based on the destination address of the IP packet to obtain the next hop router to the destination, after necessary processing, the packets are sent to the operation-level routers through corresponding interfaces. the routers along the way perform this process one by one to deliver the packets to the final destination. Routes can be manually configured by administrators, or learned from each other through dynamic routing protocols.

Traditional routers adopt centralized processing and software forwarding. A cpu completes all the functions such as route computing, table-based forwarding, and user configuration processing. The centralized processing capability of the software is obviously limited, and the data bus connecting multiple boards may also become a bottleneck, all of this makes it difficult to greatly improve the forwarding performance of traditional routers. At the same time, the network scale is further increased, and more ports need to be supported by the vro. However, generally, the vro only supports 10 ports, and even a large vro only supports 50 ports. These shortcomings will cause the router to become the bottleneck of the network and hinder the further development of the Internet.

When it is difficult to meet the requirements in a centralized manner, the architecture of the router is gradually evolving to a distributed system. Cisco's 7500 series routers use a distributed processing structure for the first time, making them a classic product in the development of data communication. This series of routers are configured with high-speed CPUs on the interface board. Each interface board is responsible for processing Input/Output packets, rather than sending them to a single motherboard for unified processing, the interface board is connected through the high-speed PCI bus, which obviously increases the packet forwarding capability and total system capacity in multiples of the number of interface boards. This makes it possible for a router to be used in a telecom network.

Since 1997, Cisco has launched a 12000 series Gigabit high-speed switching router (GSR ). The key improvement lies in the use of dedicated ASIC chips for hardware processing of packets to achieve line rate forwarding. Inter-board communication adopts an exchange structure, so that the system throughput can linearly increase with the increase of the number of link boards.

Traditional routers are characterized by storage forwarding and are considered to have low speed, unguaranteed, high latency, and high jitter. They can only be used for businesses with low requirements. The emergence of high-speed exchange routers makes a qualitative leap in the capabilities of routers. The networking capabilities and performance fully meet the needs of telecom services. At the same time, the ASIC Technology also gradually becomes applied to relatively low-end routers, improving the overall level of routers and even IP networks. In addition, the IP itself is open, flexible, and efficient, make the IP address the best choice for the three-in-one platform.

Ii. Main Features of operation-level Routers

Traditional routers connect computers to IOT platform and complete data communication. The Internet is basically non-manageable and Non-profit. It has no commitment to the network quality and has no requirements on availability, packet loss rate, or error rate, users can only accept the reality of network interruption and slow speed. With the development of network services, in addition to data communication, the IP Telecom Network will also carry voice, multimedia and other services and become an important source of network operator income, if the customer fails to meet the quality requirements or meet the user's needs, the customer will lack the minimum competitiveness and it is difficult to continue to exist. This puts forward high requirements for routers.