The Study And Design About Security Of Wireless Network's Link

Nowadays, in the computer technology productions, wireless network security is the most urgent thing, most important problem in the network development. In order to solve the problem of the security of wireless Local Area Network (WLAN), IEEE committee will define several security proposal in the IEEE 802.11 standard. However, through different testing, it is proved that the current security design could not satisfy the demand upon the applications.Therefore, with the basis of reading a large number of IEEE 802.11 standard, electronic resistance documents, Spread Spectrum communication techniques documents, referring to the security techniques of the communication in tactic communication, using the techniques of Frequency-Hopping to enforce WLANs security guarantees, and define the general design propose of the security circuit of the WLANs, designed an effective and suitable circuit. Also using new techniques to could accomplish data encryption, combined with attack detection, accomplishing the aims of upgrading the security of the WLANs systems thoroughly, and reached the effect of 3-D protection.The main outcome included the following 5 parts:1. According to WEP and TKIP algorithm, finished the encryption and decryption design model in the security circuit, also developed the imitation test program, imitated through SystemView V4.5, and accomplished the static testing and modification of that model of using MAXPLUS II software upon FPGA machine.2. Using CPLD, FPGA and other programmable machine to design and accomplish the development of WLANs Frequency-Hopping digits, synchronization of system and imitation and accomplishment.3. Combining the operating system and the techniques of attack detection, provide attack protection for secure communication, also provided better spreading ability and compatibility within the system design, connection port program, and controlling circuit.4. In an effective distant, accomplished Frequency-Hoppingcommunication through improved wireless network card. 5. Testing the function of the protection against different attacks of the original circuit that system protects against airsnort, wepcrack and other tools from influencing the wireless communication system. The testing result stated that, that circuit has accomplished the function of WEP and TKIP, could effectively protect the data security and communication security of the network, good quality of communication, outstanding effect of communication protection. At the same time, that design proposal takes less resource, system is elastic, could integrated to business-used wireless network card's chip, with a clear application value, and able to satisfy certain users whom demanded on unique LANs in the market.The thesis emphasized on data security, made research from data security to the protection of wireless connection. As TKIP is only a transition of the current RC4 algorithm, therefore, this thesis is mainly work on the design of Frequency-Hopping wireless network and accomplishment of encrypting circuit.The innovated point within the thesis is to bring the Frequency-Hopping techniques that are originally used in tactic communication into the WLANs network, enforcing the accomplishment of wireless connection security. In the present, Frequency-Hopping technologies are mainly applied on tactic communication area. In general accomplishment, the development of micro-electronic technologies, provided reliable guarantees for the accomplishment of design, therefore it is able to accomplish in actual application.