Windows QoS service quality program usage

This part of content is used for completing the configuration. After the query, I personally think the following section is a more accurate explanation of the QoS packet scheduler. We hope you can avoid detours.

The individual has successfully called the QoS application interface (API), but it does not seem to be effective (the network speed has not changed). Continue to study...

 

In the "run" dialog box, type "gpedit. run the MSC command to open the "Group Policy" window and find the "network" project under "management template". Here there is a "QoS packet scheduling" item, after expansion, you can see a "restricted and retained bandwidth" project in the "Settings" column on the right of the window. Double-click the project and you can see that the "Bandwidth limit" is 20% by default, you only need to change it to "enabled" and change the "Bandwidth limit" value to "0%" to bring the highest bandwidth usage rate."

Is it true that Windows XP retains 20% of the bandwidth for us as the optimization technique mentioned above? After 20% is changed to 0%, is it possible to speed up the Internet access? Of course, the answer is no. Next, let's take a look at how Microsoft explains this problem.

QoS Problems in Microsoft's kb316666 knowledge base are explained as follows:

Like Windows 2000, in Windows XP, a program can also use QoS through the QoS application programming interface (API. All programs can share of the network bandwidth, except for programs that require bandwidth priority. Other programs can also use this "Reserved" bandwidth, except for the request programs that are sending data. By default, the total bandwidth reserved by the program can reach 20% of the basic link speed of each interface of the terminal computer. If the data volume sent by the program with the reserved bandwidth is not completely used up, the unused portion of the reserved bandwidth can be used for other data streams on the same host.

In Microsoft's kb316666, it is clear that many published technical articles and newsgroup articles have repeatedly mentioned that Windows XP generally reserves 20% of the available bandwidth for QoS.

First, let's clarify what the true meaning of QoS is. The Chinese meaning of QoS is: the quality of online services. Specifically, it refers to various communication or program type priority technologies applied on the entire network connection. The existence of QoS technology is to achieve better network service quality. QoS is a set of service requirements. The network must meet these requirements to ensure proper service-level data transmission.

The implementation of QoS allows real-time applications such as network TVs and Network music to use network bandwidth most effectively. Because it can ensure that a guaranteed level has sufficient network resources, it provides a service level similar to that of a dedicated network. It also provides a means to notify the application of resource availability, so that the application can modify requests when resources are limited or used up. The purpose of introducing QoS Technology in Windows XP is to establish a guaranteed transmission system for network communication.

From the above Microsoft's explanation of QoS, we can know that by modifying QoS 20% to 0% in the Group Policy Editor, the goal of optimizing network performance is not met. The modified 20% parameter in the group policy refers to the maximum bandwidth that can be used when a program needs to access the network using the QoS API. If we set it to 0%, this means that applications written using QoS APIs have to compete for limited bandwidth with other applications. The possible consequence is that data that requires priority communication is not given priority. From this point, modifying QoS 20% to 0% is not only beneficial but also prevents some real-time network applications from using network bandwidth effectively. Therefore, this so-called optimization technique is misleading.