Proxy Server is an important security function. Its work is mainly in the dialogue layer of the Open Systems Interconnection (OSI) model, which acts as a firewall. Proxy servers are mostly used to connect to INTERNET (internet) and INTRANET (local area network).
![2856906_porxy[1].gif](http://m.saza.net.cn/upload/default/20181018/2969351db8c3ac4a28fc05f1e4eedd1a.gif "2856906_porxy[1].gif")
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In general, when we use a web browser to directly connect to other Internet sites to obtain network information, we directly contact the destination site server, and then the destination site server sends the information back. The proxy server is another server between the client and the web server. After it is used, the browser does not directly go to the web server to retrieve the web page but sends a request to the proxy server, and the signal is sent to the proxy server first. The proxy server retrieves the information needed by the browser and sends it to your browser.
Enter the address of the website you want to visit in the URL box, click on the proxy to open a new window to link the proxy server, wait a few seconds, if there is an error such as unable to link the server at this time, please try to select another server on it. Because the proxy server consumes a lot of resources and is time-sensitive, sometimes it cannot be opened, and the proxy server must be tried multiple times. Automatically update the latest available servers every day.
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Most proxy servers have a buffering function, just like a large Cache, which has a large storage space, and it constantly stores the newly acquired data into its native memory, if the data requested by the browser is in it. The machine's memory already exists and is up-to-date, so it does not re-fetch data from the Web server, but directly transfers the data on the memory to the user's browser, which can significantly improve browsing speed and efficiency.
More importantly: the proxy server is an important security function provided by the Internet link-level gateway (Gateway). Its work is mainly at the dialogue layer of the Open Systems Interconnection (OSI) model, which acts as a firewall.
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What is a proxy server? For the above reasons, proxy servers are mostly used to connect to INTERNET (Internet) and INTRANET (Local Area Network). In China, the so-called China Multimedia Public Information Network and Education Network are independent large-scale national-level local area networks, which are isolated from the Internet. For various needs, some groups or individuals have opened proxy servers between the two networks. If we know the addresses of these proxy servers, we can use them to reach foreign websites.
