What is the weakness of wireless LANs?

Answer 1

• Security - since a wireless LAN doesn't require users to be physically connected to a network attachment point like a wall socket or router, protecting the network from unauthorized users and locating unauthorized users becomes slightly more difficult. Wireless access points generally offer encryption options, but require configuration.
• Speed - even modern wireless LAN standards such as 802.11n can only offer theoretical maximum speeds of up to 108 Mbps (2x2 MIMO or 40 MHz channel bonding) or 600 Mbps (4x4 MIMI with 40 MHz channel bonding--highly unrealistic), while in practice they can achieve only 10s of Mbps. Modern ethernet standards can consistently offer low-latency connections at speeds of 10s of Gbps.
• Shared Medium - since the wireless medium is shared by all wireless networks in the same area, it is becoming more and more likely that users speeds will become severely decreased due to contention between many clients. In wired LANs, the medium is much more private and this contention is much reduced.