Wireless Internet access with Windows XP bridge function

The original desktop computer in the author's home, and has access to the Internet through the form of ADSL Modem + network card, recently added a laptop computer, how to make this laptop Internet access makes the author a big headache. The most straightforward and efficient solution is of course to buy a wireless router that can support both wired and wireless Internet access, but the price of wireless routers is high. When I was in a dilemma, I accidentally discovered the newly added bridge function in Windows XP. Speaking of the bridge should be an old concept, the bridge is like a switch with only two ports, you can connect two physical network segments. A typical hardware bridge is actually a computer that contains a CPU, memory, and two network interfaces. The Windows XP system simply uses software to simulate the function of the hardware bridge. Using the bridge function, I only need to add a wireless network card to the original desktop computer, can communicate with the wireless network card of the laptop, and then set the wired network card and wireless network card on the desktop as a bridge, then the wired network and wireless The network is bridged together to enable wireless Internet access for laptops. Currently, all wireless network cards sold in the market adopt the IEEE 802.11b standard, and support an Ad Hoc connection between the network card and the network card and an infrastructure connection between the network card and the access device. And the price of some brands of wireless network cards has dropped to less than 200 yuan. The first step is to purchase a wireless network card. After installing on the desktop, there will be a “Wireless Network Connection” icon in the “Lan or High Speed ​​Internet” project on the control panel (Figure 1). Step 2, Install Wireless The management tool that comes with the network card, set the connection parameters. Although the management tools interface of the wireless network card is different, the setting items provided are basically the same. The most important setting items include network mode, domain name (SSID), transmission rate and channel (Figure 2). Since there is no access device, only communication between two wireless network cards is needed, so the network mode can be set to the peer-to-peer network mode, and the domain name and channel of the two wireless network cards must be the same, and the transmission rate is in automatic mode. In general, after setting up the above items, you can find the other computer using the search function in the management tool (Survey). The third step is to create a bridge. Select "Local Area Connection" and "Wireless Network Connection" under the "Lan or High Speed ​​Internet" item of the network connection, right click and select "Bridge" in the pop-up menu. The system will automatically create a network bridge and the original two The connections go under the newly created "Network Bridge" project (Figure 3). The fourth step is to set the IP address, gateway address and DNS server address on the laptop's wireless network card and desktop bridge. Because ADSL Modem generally has a built-in IP address, you need to assign an address to the same network segment of the two computers. The gateway address is the IP address built into the ADSL Modem. The DNS server address is still used when installing broadband. The address provided by the department. Everything is ready, pick up the laptop, and wirelessly connect to any location in a 90 square meter room. Of course, due to the signal strength of the wireless network card itself, the signal is weak when the distance is long. After a simple download test (using network ants), the fastest download speed is generally 70KB~80KB per second when the signal is best. The weakest is about 15KB per second. The biggest problem with this type of wireless Internet access is that you need to turn on your desktop at the same time when your laptop is online. In addition, the author finds that because the bridge is waiting for a frame to be completely received and verified after the data frame is forwarded, the speed of the Internet is slightly slower than that of the software agent. This way is good, no need to install additional software and hardware, the setup is simple, for users who often need to use the laptop wireless Internet access, this connection is still very economical and convenient.