Wireless security for local area networks has improved over the years and now provides reasonable security for organisations using WLANs. As with any technology, there are advantages and disadvantages involved in using wireless security on your LAN. A good understanding of both can help you make a wise decision when implementing your wireless local area network.
Data encryption is the primary method of securing a wireless LAN, and encryption takes machine cycles and bandwidth. Encryption is a mathematical algorithm that is processor-intensive, and the process of encryption produces a much larger packet than the unencrypted original text. The encryption process negatively impacts each computer's performance either on the main CPU or the processor on the network card. The larger encrypted packets negatively impact overall network performance. For unsecured networks there is no performance impact, so the performance impacts of security are a disadvantage.
The most obvious advantage of wireless security is that it provides the confidentiality that you want for your personal or business data. A properly secured wireless network provides a user with confidence that his network and the information travelling on it are secure from hackers.
The implementation of wireless security can be both an advantage and a disadvantage. For small networks, such as ad hoc wireless networks, implementing security is not difficult at all and this is a huge advantage. However, for a business with a hundred users and multiple wireless access points, setting up security takes some time, effort, knowledge and money. Most businesses that set up a wireless network do so for the flexibility that it gives, and are willing to endure the disadvantages that come with implementation.
Wireless networks can employ different encryption schemes from WEP, which is the oldest, to WPA2, the newest. This is good in that older computer operating systems can be accommodated on the network, but the disadvantage is that WEP is less secure than WPA2 and only one encryption scheme can be used on a wireless network at a time. If you have to support older operating systems, you have to use the less secure encryption algorithm, which is a big disadvantage. In this case it is best to upgrade the operating systems and use the most advanced encryption available.