This is a topic that people often discuss. It is undeniable that IEEE 802.11g has great advantages in performance. The 54Mbps transmission rate can meet the high bandwidth requirements of network applications. However, in my opinion, IEEE 802.11b is still the best economic option for building a home wireless LAN. Although its transmission rate is only 11Mbps (the actual value is 500~600kB per second), this speed is still higher than the access speed of common broadband types such as DSL and LAN, and it can fully meet the needs of home users for wireless broadband sharing Internet access. . Since wireless networks are not limited by geographic location like wired networks, as long as there is a convenient place for wireless signals, security issues have attracted much attention. Although the privacy requirements of home wireless networks are not as stringent as those in the commercial field, in the face of increasingly crowded network speeds, no one wants to share their limited bandwidth with unfamiliar people. Therefore, home wireless networks should also choose suitable encryption methods. . There are two main comparisons: One is 64-bit/128-bit WEP data encryption. This method is highly secure, but due to the consumption of some wireless network bandwidth during the encryption/decryption process, the transmission speed of valid data may be affected. The second is to turn off the SSID wireless identification of the AP, so that the SSID indication of the wireless network will not appear in any available network connection. The user can only connect after entering the SSID, and the SSID of the AP can be arbitrarily changed when managing the AP. (Similar to the login user name and password entered in the login mailbox), this method also plays a role of “encryption†without losing the transmission speed, effectively preventing the invasion of unauthorized users, and is the best protection for home wireless networks. Measures. What is the initial verification password? As mentioned above, most of the current APs provide web-based management. When the user enters the management interface for the first time, he needs to enter a user name and password (as shown in Figure 3). Under normal circumstances, the manufacturer will indicate the AP's default user name and password in their product description. If you are buying second-hand products and no instructions are available, then only go to the manufacturer's homepage to download the corresponding product manual. For those wireless APs that have been set up with special account numbers and passwords by the "previous owner," they can be restored to their default values ​​using the "Factory Reset Key." How to put it in place? The placement of APs is also scientific. Wireless signal is essentially a kind of RF signal. There is interference problem. Antenna is also a directional element. It can only radiate high-intensity energy in a certain direction. Therefore, the antenna is placed in the position of wireless AP. Placement positions will, to a large extent, affect the effect of the RF field shape, which will affect signal quality and signal strength. For this purpose, the placement of wireless APs should be as wide and open as possible. In general, the “centered†position is the best location for the best signal coverage. According to the actual situation, 100 square meters or less are generally two bedrooms and one bedroom. When the wireless network is laid out, the wireless AP is placed in the living room or in the intersection of several rooms. The effect is most ideal, and signals placed in other rooms will be Worse. Units of 150 square meters or more, such rooms are generally more complex, and the wireless gateway is also placed at the intersection with the best effect, placed in other rooms, and the signals need to be tested before they can find out the wireless signal dead angle. How to check the signal strength? If the computer is using the Windows XP or Windows 2000 operating system, just click on the wireless network status icon in the task bar when the wireless network is connected, you can know the strength of the wireless signal, which is the most intuitive detection method. In addition, most wireless PCMCIA interface cards currently on the market are equipped with special management software to match them. With this, wireless network status can be queried in detail and various function parameters can be set. Taking Lucent ORiNOCO as an example, through its own ORiNOCO Client Manager management software, it can achieve signal viewing, channel selection, wireless encryption and other functions, and it is also very convenient to set up. And some brand computers are equipped with special management software tends to be more powerful, such as the IBM ThinkPad notebook computer, using IBM Access Connection software and wireless network card, wireless signal strength detection can be accurate to 1%. What should I do if the signal is weak? This is a problem that every network user may encounter, which is mainly reflected in poor signal quality and unstable data transmission. In general, it can be improved by adding external antennas, setting up radio channels, and adjusting the placement of wireless APs. If the above solution does not solve the problem, you should consider refreshing the firmware of the wireless network card and upgrading the driver. Is there interference with the home wireless network? This is for sure. The material of the room wall, the furnishings of the furniture, and even the opening and closing of the door can all affect the wireless signal. Since the operating frequency band of 802.11b/g is 2.4Ghz, and the frequency band of many devices in industry is just in this frequency band, 802.11a is much better in terms of anti-interference performance. It is also worth noting that the mobile phone signal has a relatively large interference to the wireless network, so it should be kept away from the storage point of the wireless AP as far as possible in order to avoid affecting the connection quality of the wireless network.
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