  The rapid proliferation of wireless networks and mobile computing
applications has changed the landscape of network security,the wireless
networks have changed the way business, organizations work and offered a new
range of possibilities and flexibilities; It is clear that wireless solutions
are transforming the way we work and live. Employees are able to keep in touch
with their e-mail, calendar and employer from mobile devices, but on the other
hands they introduced a new security threats appeared. While an attacker needs
physical access to a wired network in order to gain access to the network and
to accomplish his goals, a wireless network allows anyone within its range to
passively monitor the traffic or even start an attack,one of the
countermeasures that can be used is the intrusion detection systems in order to
allow us to know both the threats affecting our wireless network and our system
vulnerabilities in order to prevent those attackers, the IDS its main purpose
is to manage the system and its operations and Its duty depends on .
