The security of Wireless Access networks is a topic that people have always been concerned about. Many people may not understand the shortcomings of Wireless Access Networks in encryption technology. It does not matter. After reading this article, you must have gained a lot, I hope this article will teach you more things. In the wireless access network field, which has been accused of eavesdropping and illegal use, a new security technology has emerged. This is the "WPAWi-Fi protection access" developed by the Wi-Fi Alliance, an industry group engaged in Wireless Access Network product authentication )". A few days ago, the certification test has been started. products that pass the certification will be available soon. Next, I will analyze the working principle of WPA to see if the wireless access network is more secure.
In the past, wireless access networks were not secure because there were some shortcomings in the standard encryption technology WEP.
WEP is a technology that encrypts the group information in the "RC4" way between the Access Point and the client, and the password is easily cracked. The encryption key used by WEP includes a 40-bit or 104-bit pre-defined by both sending and receiving sides. It is also the 24-bit, known as the IV key, that the sender determines for each group's information. However, in order to notify the communication object of the IV key, the IV key is directly embedded into the group information and sent out without being encrypted. If you listen through the wireless access network, collect and parse the group information containing the specific IV key, even the secret's universal key may be calculated.
WPA is a new technology that inherits the basic principles of WEP and solves the disadvantages of WEP. Because the algorithm for generating encryption keys is enhanced, even if the group information is collected and parsed, it is almost impossible to calculate a general key.
Specifically, the principle is: according to the general key, together with the serial number indicating the computer MAC address and group information, different keys are generated for each group information. This key is then used for RC4 encryption like WEP. Through this processing, the data exchanged for all group information of all clients is encrypted by different keys. No matter how much data is collected, it is almost impossible to crack the original universal key.
WPA also adds functions and authentication functions to prevent data tampering in the middle. With these features, all the shortcomings that were previously criticized by WEP have been solved. Of course, there may be other security flaws in WPA. But not yet found. Currently, WPA is sufficient to ensure the security of wireless access networks.