A brief discussion on the development history and future trends of routers

Labs Guide

As a common network device, routers can support various LAN and WAN interfaces and are mainly used to interconnect LANs and WANs, enabling communication between networks with different structures and logical separation. Over the past thirty years, routers have developed steadily to meet users' needs for higher bandwidth and faster Internet.

Part 01, Introduction to Routers

A router is a special network device that is used to connect multiple networks with different structures and logically separate. The router mainly includes two mechanisms: routing and forwarding. It can calculate the best routing path for data packets from the sender to the destination and forward the packets. With the development and popularization of the Internet, routers, as one of the important components of network infrastructure construction, have special importance to the development and application of the network.

Part 02, Development History of Routers

Since Cisco launched the world's first commercial router in 1986, more than 30 years of development have seen the emergence of five generations of milestone routers.

First generation router: the world's first commercial router (AGS)

In 1984, Leonard Bosack and Sandy Lerner founded the famous Cisco company in San Jose. Two years later, they launched a product called "Access Gateway Server (AGS)". As the name suggests, a multi-protocol router allows data to be transmitted smoothly between computer networks using different protocols. In this way, the originally incompatible computer networks are connected together by the router. At this time, the router does not support too many network connections, and the business it needs to process is relatively small, so there is no high requirement for its data processing capabilities.

Second-generation routers: Cache technology

As the scale and traffic of networks increase, more network interfaces are needed, and the burden on the router CPU and bus is getting heavier. To address this problem, technicians introduced cache technology in the network interface card of the router. The starting point of this technology is that most users usually access a small number of commonly used networks, so these commonly used routing information can be cached on the service interface card through cache technology. In this way, most messages can be directly forwarded through the routing table cached in the cache, greatly reducing the burden on the router CPU and bus.

Third-generation routers: Routing and forwarding separation technology

At the end of the last century, the advent of Web technology has enabled the Internet to develop more rapidly, and users are no longer limited to accessing a few commonly used networks. Therefore, it is no longer as easy to find routing information from the cache as in the past, and the bottleneck problem of the router CPU and bus has once again become the focus. To address this problem, the third-generation routers introduced a fully distributed technology - separation of routing and forwarding. Among them, the main control board, as the center of this structure, coordinates the management of equipment, collects and calculates routing information, and sends the calculated forwarding table to each business board, while the business board uses the routing forwarding table to implement specific routing forwarding functions. The routing forwarding of the business board is completely independent of the main control board, and multiple business boards run in parallel, which effectively improves the performance of the router.

Fourth-generation routers: ASIC distributed forwarding technology

In the post-Web era, with the unprecedented development of the Internet, network traffic has grown exponentially. In the past, software-based IP router technology could not meet the bandwidth requirements, so ASIC distributed forwarding technology emerged. ASIC is the abbreviation of Application Specific Integrated Circuit. ASIC distributed forwarding technology is based on hardware switching technology, which uses hardware to implement the forwarding process. ASIC hardware forwarding chip contains multiple hardware tables and search engines, which can quickly find information such as routing tables in the device, and it also has adaptive capabilities, which can automatically adjust the capacity of hardware tables and search engines to cope with changes in network traffic.

Fifth-generation routers: NP technology

At the beginning of the 21st century, the business capabilities of routers became the focus of manufacturers. In order to solve the defects of basic IP networks, new technologies such as network management, business management, VPN and IP-QoS were introduced into routers. In terms of business process processing, this generation of routers also introduced NP technology designed specifically for IP networks. NP (Network Processor) has programmable capabilities and is widely used in scenarios such as packet processing, protocol analysis, route lookup, firewall and QoS. It has many similar design concepts to GPU and can complete computing tasks in parallel through several optimized and efficient microprocessors. In addition, NP also includes some hardware coprocessors that can handle complex operations such as traffic scheduling algorithms, QoS congestion control algorithms, routing table lookup algorithms, etc., to effectively improve the processing performance of routers.

Part 03, Future Development Trends of Routers

3.1 Intelligent Routing Will Continue to Develop

As more and more smart terminals are connected to the Internet, users have put forward requirements for faster, more stable and more secure networks, and traditional routers can no longer meet the further needs of users. The emergence of intelligent routers has realized the intelligent management of devices and networks. It can collect, calculate and analyze data from different smart terminal devices and feed back the results to users, thereby improving the quality of service. The development of smart routers requires the support of technologies such as big data analysis, machine learning, and cloud computing, as well as a high degree of integration of software and hardware. As the center of the home network and the entrance to all traffic, the future smart router will have the ability to control smart terminals and security protection, becoming the center of home media and smart homes.

3.2 Router converged network platform will have new developments

With the rapid development of mobile Internet, routers are no longer limited to providing data transmission services for simple network connections, but also need to combine themselves with more network services to realize more real-time network applications. Router convergence network platform will become a new direction for the development of routers, combining multiple network services to realize and support more real-time network applications and management services.

3.3 New opportunities and challenges brought by WIFI6

WiFi6 is the sixth generation of wireless network technology and a wireless LAN technology created by the WiFi Alliance based on the IEEE 802.11 standard. Compared with WiFi5, WiFi6 has the advantages of higher data transmission speed, better performance and connection stability, support for more devices, and lower power consumption, which will significantly improve the user experience. In the future, WiFi6 will be promoted and applied to various scenarios such as home networks, enterprise networks, and public places. For example, WiFi6 technology allows more devices to be connected to the home network at the same time without worrying about network delays and channel conflicts. In high-density public places such as airports, hotels, and shopping malls, WiFi6 can provide faster response speeds and more stable connections, thereby solving network congestion and signal interference problems. Thanks to the development of WiFi6 technology, more information-based, intelligent, and multi-terminal collaborative applications will be generated in the future.

Part 04: Summary

Since Cisco launched the world's first commercial router in 1986, after more than 30 years of development, five generations of milestone routers have emerged. The emergence of cache technology, routing and forwarding separation technology, ASIC distributed forwarding technology, and NP technology has made the performance of routers soar, effectively coping with the explosive growth of network traffic in the Internet era. In the future, routers will have a longer-term development in the direction of intelligent routing, network platform integration, WiFi6, etc.