Comprehensive Performance Evaluation of low-end and high-End Routers

At present, the routing technology is developing rapidly, and the performance of routers is getting higher and higher. "low-end routers and high-end routers are similar in usage. Why is the price so far apart ?"

In fact, this question is very good, and many friends who are not familiar with the product and technology will basically have similar questions-"Why is this router so expensive with the same functions, another one is so cheap. "Why is Cisco's vro so expensive? And TP-LINK is so cheap ?" "The two vrouters have the same performance parameters. Why is the performance so far different ?" For these problems, we must start with the basic principles of routers.

How routers work

The simplest network can be imagined as a single-line bus. Each computer can send packets to the bus to communicate with each other. However, as the number of computers in the network increases, this is not feasible and may cause many problems:

1. bandwidth resources are exhausted.

2. Each computer wastes a lot of time processing unrelated broadcast data.

3. The network becomes unmanageable, and any errors may paralyze the entire network.

4. Each computer can listen to communications from other computers.

Network segments can solve these problems, but at the same time, you must provide a mechanism for computers in different network segments to communicate with each other, that is, to promote devices like routers: routers work at the IP network layer, used to forward data between subnets. Vrouters generally have multiple network interfaces, including local network interfaces and wide area network interfaces. Each network interface connects to a different network. The router records the network information connected to each network port. At the same time, a route table is stored in the router, which records the port numbers to be sent to different network addresses. The communication information of various information services used by Internet users can all be attributed to information transmission in units of IP packets. In addition to the data information to be transmitted, it also contains the destination IP address to be sent, the source IP address to be sent, and some related control information. When a router receives an IP packet, it searches for the route table based on the destination IP address in the packet and sends the IP packet to the corresponding port based on the search result. The next IP router continues forwarding after receiving the packet until it is sent to the destination. Routers can exchange route information through the routing protocol to update the route table.

Factors Affecting vro Performance

After the above introduction, we may not know much about the work of the router, but it doesn't matter. This is not our purpose. We mainly want to explain it to you, the working principle of the router determines that it must use a chip to complete some necessary judgment and data packet forwarding, which is done by a processor, various data packets to be processed or processed exist in the memory. Therefore, the processor's operating frequency and memory capacity determine the performance of a vro to a large extent.

However, the performance of the vro cannot fully depend on the processor frequency and memory capacity. However, the performance of the vro is poor, but the performance of the vro is not necessarily good; the processor clock speed is only a performance indicator of the processor. Its bus width (16-bit or 32-bit), Cache capacity and structure, internal bus structure, single CPU, multi-CPU distributed processing, computing mode, and other indicators will affect the performance of the processor. Almost all routers use a communications-related CPU. Therefore, "using a communications-related CPU" is equivalent to saying nothing. The key lies in what kernel is used by the CPU and the internal structure. The same is true for the memory. The size of the memory does not matter. If the load is not large, there may not be much difference between the 4 M memory and the 8 M memory, therefore, it is not scientific to judge vro performance based on the memory size.