What is a sock5 proxy and an HTTP proxy (post)

The proxy server stands for proxy server. Its function is to obtain network information from the proxy network user. It is a transfer station for network information. In general, when we use a web browser to directly connect to other Internet sites to obtain network information, we must send a request signal to obtain the answer, and then the other Party sends the information back in bit mode.

The proxy server is a server between the browser and the Web server. With this server, the browser does not directly go to the Web server to retrieve the web page, but sends a request to the proxy server, the request signal will be sent to the proxy server first. The proxy server will retrieve the information required by the browser and send it to your browser.

In addition, most proxy servers have the buffer function, which is like a large cache, which has a large storage space and constantly stores new acquired data in its local memory, if the data requested by the browser already exists and is up-to-date on its local memory, it will not retrieve data from the Web server again, directly transfer the data in the memory to the user's browser, which can significantly improve the browsing speed and efficiency. More importantly, the proxy server is an important security function provided by the Internet link-level gateway. It mainly works in the Open System Interconnection (OSI) the dialog layer of the model. Main functions include:

1. Break through its own IP address access restrictions and access websites outside China. CERNET, 169, and other network users can access foreign websites through proxy.

2. access resources in some organizations or groups, such as a University FTP (provided that the proxy address is within the permitted access range of the resource), use the free proxy server of the address segment in the education network, it can be used to download and upload various types of FTP files open to the education network, as well as various types of data query and sharing services.

3. Break through China Telecom's IP address blocking: many websites of China Telecom users are restricted to access. Such restrictions are artificial, and the address blocking by different serve is different. So you can try another Proxy Server outside China when you cannot access it.

4. increase access speed: Usually the proxy server sets a large hard disk buffer. When external information passes through, it is also saved to the buffer, when other users access the same information again, the information is directly retrieved from the buffer and transmitted to the user to Improve the access speed.

5. Hide real IP addresses: netusers can also hide their own IP addresses in this way to avoid attacks.

Sock5 Proxy Server:

The proxy and the proxy server communicate with each other through the "sock4/5 proxy protocol" (For details, refer to the RFC documentation ). The sock4 proxy protocol can be said to strengthen the HTTP Proxy protocol. It not only acts as a proxy for the HTTP protocol, but also acts as a proxy for all external connections, without protocol restrictions. That is to say, as long as you connect to the outside, it will give you a proxy, regardless of what protocol you are using, which greatly makes up for the shortcomings of the HTTP Proxy protocol, this allows you to use many network software that cannot be used by HTTP proxy. (For example, OICQ, MSN, and other software) The sock5 proxy protocol has modified the previous version and added support for UDP proxy and identity authentication. It is not a "protocol proxy", so it will proxy all connections, regardless of what protocol is used.

HTTP Proxy:

HTTP is the most widely used communication protocol for information transmission over the Internet. Some local networks impose restrictions on the Protocol and only allow users to access external websites through the HTTP protocol.

 

This article is transferred from Netease Institute