WEB ANNOUNCE::

Use wireless network common attack and safe countermeasure

From;    Author:Stand originally
One, the attack with wireless common network and weakness

The attack cent that wireless network may get is two kinds, one kind is the charge that about secret of network visit control, data the gender is protected and data integrality protection has. This kind of attack also can happen below wired environment; Another kind is decided by the character of wireless medium itself, be based on wireless communication network the charge that design, deploy has with maintenance distinctive pattern.

The weak point that be in is put in 1 WEP

IEEE (Institute OfElectrical And Electronics Engineers, electric learn with electronic engineer) the 802.11 standards that establish are the earliest released 1999, it described WLAN (Wireless Local Area Network, wireless local area network) with WMAN (Wireless Metropolitan Area Network, net of wireless city land with certain boundaries) MAC (Medium Access Control, medium visits control) the standard with physical layer. To prevent to appear the circumstance of accidental eavesdrop mixes wireless network user offer as equivalent as the function in wired network safety precaution, IEEE introduced WEP (Wired Equivalent Privacy, wired equivalence is confidential) algorithmic. With a lot of new technologies, the WEP of original design was discovered by people a lot of serious weaknesses. Experts exploit the weakness that has discovered, breach all safety that WEP claims to have control a function. As a whole, WEP puts in following weaknesses:

1) integral design: In wireless environment, using confidential measure have very big risk, but a WEP agreement is 802.11 equipment implementation only optional.

2) add close algorithm: The IV in WEP (Initialization Vector, initialization vector) because digit is too short,design with initialization restoration, appear easily phenomenon of put sb in a very important position, be defeated to decode key thereby. And close to be being used at undertaking drifting adding RC4 is algorithmic, in its the close key with a 256 byte medium data exists weakness, still did not have plan of any a kind of implementation to correct this flaw at present. In addition the CRC that is used at having integrality desired result to proclaimed in writing (Cyclic Redundancv Check, the loop is redundant desired result) can ensure data is transmitted correctly only, can not make sure its were not revised, the desired result that is not safety piles up ridge.

3) close key management: 802.11 standards point out, the close key that WEP uses needs to accept exterior the control of system of close key management. Pass exterior control. Can reduce the conflict amount of Iv, make wireless network hard breach. But the problem depends on this process form very complex, and need manual operation. Consequently the deploy of a lot of networks person more apt is used default WEP close key, this nigrify guest decreased greatly to cut the workload that decodes key place to make. Another some of advanced solution needs to use additional resource, be like the LEAP of RADIUS and Cisco, it is very costly that its are cost.
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