LAN Proxy Server Building Scheme Tutorial _ Proxy Server

A proxy server is a computer that is not able to perform an operation on its own, which is the proxy server that performs the operation through a single server. The proxy server is the network Service technology which comes into being with the Internet, it can realize the security filtering of the network, the flow control (reduce Internet usage fee), the user manages and so on function, so the proxy server is very useful to the user of the home network, small enterprise network. It can not only solve many units connected to the Internet caused by insufficient IP address, but also to speed up the client access to network resources, control network traffic and save the cost of the Internet, and even as a primary network firewall use, cut off illegal access to information, block the general hacker intrusion local LAN.
　
Proxy server can realize the functions are: sharing Internet, firewall, user management, control flow and so on.
　
　 　　 1. Share the Internet, save IP address
　
When connecting to the Internet, all clients apply for 1 IP addresses, but the IP address partition cannot meet the user's expectation of connecting to the Internet, which can be resolved if a proxy server is used. Start by connecting the computer that needs to be connected to the Internet to a local area network, and then connecting to the Internet through a proxy server, which allows multiple computers to share an IP address on the Internet, that is, a total of one outlet connected to the Internet, This will be able to save the maximum IP address, but also to save the company, the unit Internet costs (node occupancy fees, depreciation fees and so on).
　
　 　　 2. Reduce export flows
　
Many users use proxy server mainly to solve the problem of sharing the Internet, but it also has an important function is to reduce unit export traffic. A proxy server provides a larger cache for users, and when a client accesses certain resources on the Internet, it stores the resources that are accessed in the cache, and the proxy server automatically reads the same information from the cache when other clients need to browse the same message. Therefore, all users through the proxy server can share these access resources, which can greatly improve the client access speed, reduce the local node's export load and traffic, reduce costs, improve economic efficiency.
　
　 　　 3. User Management
　
The leadership of the unit must be a headache for how to manage employees ' internet problems. Playing games on the Internet during working hours, or chatting with QQ is really a very effective work. And if the company use Proxy server on the Internet, you can set some parameters on the proxy server, effective management of the user. Can be opened for different users of different application functions, set user permissions, such as: WWW, FTP, Telnet, e-mail and so on. can also set up in the proxy server QQ, ICQ and other network application software user rights. You can also filter some sites on the Internet to give users access to only one IP address segment or domain-wide information.
　
　 　　 4. The firewall function of the proxy server
　
Firewall technology is a new network security technology developed and popularized in recent years, it is a system that implements the access control strategy between each network, can filter illegal information flow, but also can allow legal communication. Using proxy server can realize firewall function to a certain extent.
　
The above illustrates the use of a proxy server for LAN Internet usage. In fact, we need the proxy server is the general computer on the installation of Proxy Server software, the popular has Wingate, Winroute, Sygate and so on. These software have their own characteristics, the proposed use of Wingate, not only because of its powerful and comprehensive, but also because the Wingate is a veteran proxy server software, many domestic users, can immediately get technical experts support and help.
　
　 　　 Wingate Classic Configuration
　
Before the beginning of this article, let's talk about the operating environment of Wingate. Wingate is the best platform for Windows 2000, although it can work on Windows 98, but the stability is poor, and can not resolve the machine name, only display IP address, for real-time monitoring management is not convenient. Wingate's download address is http://www.wingate.net, software installation is very convenient, as long as the "Next", the final finish on the line. After reboot, an icon appears in the status bar, blue indicates that it is working, and red indicates a stop or an abnormal error.
　
　 　　 1. Client Browsing Web page
　
In fact, the Wingate Agent service has been able to work, as long as the dial-up connection can make the LAN Internet access. If you want to use IE to browse the Web, take IE5.5 as an example, just fill in the IP address of the proxy server in the menu "Tools", "Internet Options", "Connection", "LAN Settings", and the port defaults to 80 (you can change).
　
　 　　 2. E-mail Settings
　
As is known to all, general e-mail receipts Use the POP3 (Post Office Protocol 3) Protocol, and the credit SMTP (Simple Mail Transfer) protocol is issued. The port corresponds to 110 and 25,wingate, which provide support at the same time, in the Wingate main interface to the "services" bar, you can see that it lists a number of services, including POP3 Proxy Server, the port defaults to 110.
　
The following set POP3 receiving client, I use foxmail here, NetEase free mailbox 163.com for example. Fill in the IP address of the proxy server in the mail receiving server, when the user name fills in, note that the input format is "username #pop3 server Address", for example "email#pop3.163.com". If your agent uses non-standard ports, you can change them in the client software, advanced options.
　
Wingate Initial installation does not take the SMTP service, we can add by hand: in the "Service" field, click the right mouse button, "New services," Select the SMTP Proxy service, and then double-click the SMTP Proxy service, you will see a pop-up window, in the "General" Support for sending email via ISP mail Server "on the hook, since many of the free sending servers send only the mail in this domain, the reply to the address is not the domain of the mail will automatically retreat, so here you can fill in the mail address of the local ISP, the client as long as the letter server changed to proxy server address.
　
　 　　 3. QQ Chat Settings
　
Many friends say using Wingate to do proxy server can not use QQ, in fact, set very simple: in the QQ "System parameters", "Proxy settings" check "Use SOCK5 Proxy Server", and then fill in "Proxy server address", the default port 1080 can be. IRC chat software settings in the same way, in the "Firewall" option to set the line.
　
　 　　 4. FTP Settings
　
FTP Settings and e-mail settings similar to the need to connect the FTP server address using Proxy server address, the key or in the user name format: User name @pop3 server address.
　
　 　　 5. Streaming Media playback settings
　
Nowadays many people love to watch movies online. RealPlayer, QuickTime and other software is essential to play the tool. However, to access the Internet through the Wingate Proxy Server, they also need to make some settings: in QuickTime, you need to fill in the sock and HTTP addresses in the streaming proxy option, and then select the port in Stream transport. The film can be viewed smoothly with good network conditions. The method set in RealPlayer is: Select Use the PNA server in the proxy server, fill in the Proxy server address, the port defaults to 1090. In transport, select Use specified transport, and both RTSP and Pna Select Use HTTP only.
　
　 　　 6. Download Breakpoint Renewal Settings
　
Take GetRight as an example, in the GetRight "configuation", "Internet-proxy", check "use Proxy Servers", the following are filled in HTTP, FTP and sock proxy service address and port, In the FTP proxy settings, check "use Http Protocol with FTP proxy Server".
　
　 　　 7. Prohibit access to Restricted sites
　
Create a standard condition in the Prohibit list, which is: HTTP address, Condition: included, and add the address. This will display a warning message whenever this user accesses the site and is documented in the Wingate system information.
　
　 　　 8. Prohibit downloading software
　
Because now the network can download the software format is generally zip, exe, RAR, so you can set in the "no list" three conditions for "HTTP address", "end", the specific address "zip,exe or rar" rules. This will effectively prevent users from downloading software.