When speaking of computers, a network refers to connections between at least one computer and one peripheral device — that is, a peripheral device that is not directly connected to a port, but communicated through a wired or wireless connection. A Local Area Network (LAN) is a small, confined computer network, usually within a single building, and sometimes within a single room. It contrasts with a WAN, or Wide Area Network, which covers a much larger territory. A WLAN is a Wireless Local Area Network, and WLAN monitoring refers to keeping an eye on the network for the sake of management, on the one hand, and security, on the other hand.
WLAN monitoring for the sake of network management may include keeping track of coverage, usage, and performance. Coverage refers to the reach of the network. The standard systems are 2.4 GHz (GigaHertz) and 5 GHz, which is allowed in some countries, such as the United States, but not in others, such as China. In general, 5 GHz systems, having higher frequency, have less range than 2.4 GHz systems, and may not reach throughout a facility without engaging a number of Access Points (APs). It is important to be sure that the desired coverage is maintained, and WLAN monitoring helps achieve this.
Performance is another area of WLAN monitoring. The greater spectrum that 5 GHz systems have available means better performance. On the other hand, the signal of 2.4 GHz systems may suffer from RF (Radio Frequency) interference from other WLANs, microwaves, or cordless phones, so in both instances, WLAN monitoring may serve to pinpoint performance issues. Other performance areas that are often reviewed are Access Point overload, excessive numbers of retries, high noise levels, and implementation errors.
Usage comes into WLAN monitoring for the sake of capacity planning, as well as other reasons. Usage indicators may also point to or be evidence of intrusion. This can be the case when extraordinarily high bandwidth use or use of services that are out of the ordinary are detected. An even surer sign is traffic to points that are unmanned. Monitoring for intrusion has other facets as well, including watching for unauthorized users and making sure the key is secure. Intrusion monitoring includes regular security audits, surveillance, and tracking attack and break-in attempts.