Wireless local area networks (WLANs) are become popular as they are fast, cost effective, flexible and easy to use. There are some challenges of security and for IT administrators the choice of security protocol is a critical issue. The main motive of this paper is to make the non-specialist reader knowledgeable about threats in the wireless security and make them aware about the disadvantages of wireless security protocols. WEP (Wired Equivalent privacy), WPA (Wi-Fi Protected Access) and RSN (Robust Security Network) security protocols are defined and examined here. This security protocols are compared with the common. This paper is a comparative analysis of WEP, WPA and WPA2. We have tried to perform and check authentication of all 3 protocols by implying the legendary attack vector scripts i.e. Air crack set of tools. The test was conducted on Back Track operating system which is considered as dedicated pentesting operating system. In the test result, we found out that WEP is the weakest, to which WPA was a temporary solution and WPA2 is a very solid and long term solution. This paper is a mixture of wireless security weaknesses and counter measures to the problems faced until recently. After reading this paper the non specialist reader will have complete review and awareness about the wireless security and vulnerabilities involved with it.