Wireless LAN (WLAN) is a wireless network without fixed infrastructure. Load balancing, channel assignment, handoff and its security are critical challenges due its exclusive features. There are many load balancing algorithms, channel assignment and handoff methods, secure routing protocols presented. A broadstudy of several load balancing algorithms, channel assignment and handoff methods, secure routing protocols in WLAN is presented in this paper. These are evaluated in terms of various constraintslikepacket delivery ratio, throughput, end to end delay, total energy expended, standardized routing load, packet loss cost, etc.