Basic knowledge about routers: different types of network routers

This article describes the specific knowledge of various network routes and provides details about the access routers and enterprise-level routers. I hope this article will help you.

Routers can be seen everywhere in networks of various levels on the Internet. The access network allows families and small enterprises to connect to an Internet service provider. routers in the enterprise network connect to thousands of computers on a campus or enterprise. The router Terminal System on the backbone network is usually not accessible directly, they connect ISP and enterprise networks on the long-distance backbone network. The rapid development of the Internet poses different challenges to backbone networks, enterprise networks, and access networks. The backbone network requires the vro to be able to forward high-speed routes to a few links. Enterprise-level routers require a large number of ports and a low price. They also require easy configuration and QoS.

Router basics 1. Access A Router

Connect a vro to a small enterprise customer in a home or ISP. The Access Router does not only provide SLIP or PPP connections, but also supports VPC protocols such as PPTP and IPSec. These protocols must run on each port. Technologies such as ADSL will soon increase the available bandwidth of various families, which will further increase the burden on access routers. As a result of these trends, the Access Router will support many heterogeneous and high-speed ports in the future, and can run multiple protocols on each port, while also avoiding the telephone exchange network.

Router basics 2. enterprise-level Routers

An enterprise or campus-level router connects to many terminal systems. Its main goal is to achieve as many endpoints as possible and further support different service quality. Many existing enterprise networks are Ethernet segments connected by hubs or bridges. Although these devices are cheap, easy to install, and do not require configuration, they do not support service levels. On the contrary, networks with vrouters can divide machines into multiple collision domains and thus control the size of a network. In addition, a vro supports a certain level of service and can be divided into at least multiple priority levels. However, the cost per port of the router is higher, and a lot of configuration work is required before it can be used. Therefore, the success or failure of an enterprise router lies in whether a large number of ports are provided, the cost per port is low, whether it is easy to configure, and whether QoS is supported. In addition, enterprise-level routers are required to effectively support broadcast and multicast. Enterprise networks also need to deal with various legacy LAN technologies and support multiple protocols, including IP, IPX, and Vine. They also support firewalls, packet filtering, and a large number of management and security policies and VLANs.

Router basics 3. Backbone Router

Backbone routers enable enterprise-level network interconnection. The requirements for it are speed and reliability, and the cost is secondary. Hardware reliability can be achieved through technologies used in the telephone exchange network, such as hot backup, dual power supply, and dual data path. These technologies are almost standard for all backbone routers. The main performance bottleneck of a backbone IP router is the time it takes to find a route in the forwarding table. When a packet is received, enter the port in the forwarding table to find the destination address of the packet to determine its destination port. When the packet is shorter or the packet is sent to many destination ports, it is bound to increase the cost of Route Search. Therefore, placing some frequently accessed destination ports in the cache can improve the routing search efficiency. Whether it is an input buffer or an output buffer router, there is a bottleneck in route search. In addition to performance bottlenecks, the stability of routers is also a common concern.

Router basics 4. Too-bit Router

Fiber optic and DWDM are mature and ready-made among the three main technologies used by core internet in the future. If there is no router corresponding to the original bandwidth provided by the existing optical fiber technology and DWDM technology, the new network infrastructure will not be able to fundamentally improve the performance, therefore, the development of high-performance backbone switches/routers, too-bit routers, has become an urgent requirement. The Tbit router technology is still in the development experiment stage.