A network traffic monitor examines the usage of a Local Area Network (LAN) and gives display information of download and upload statistics. The main function of a network traffic monitor is to count and monitor the IP traffic between the Internet and LAN. One of the most common functions of a network traffic monitor is to monitor the bandwidth usage of firewalls, routers and leased lines. Network traffic monitors register and monitor every new dial-up connection, and can upload and download traffic of computers. It displays all the details of incoming and outgoing traffic of the last 10 minutes on the link. These 10 minutes adds up to hours, and this information is saved in computer for further analyzing.

A network traffic monitor informs which applications in a machine are causing how much network traffic, and over which IP port this traffic is occurring. It can identify peak usage hours, application usage and more. A user can view details on the host, recent traffic patterns and applications that are generating network traffic. A network traffic monitor, with just a few clicks, shows everything that passes through the networks pipes. One can easily filter the network traffic to concentrate on certain information that is much needed.

A network traffic monitor debugs new applications that involves network communication and troubleshoots network related problems. Some network traffic monitors have technology that allows the decoding and restoring of network traffic in an easy format, so that even a novice user can understand it. A network traffic monitor can track the entire process of incoming and outgoing traffic, all uploads and downloads, instant messaging conversations, sent and received e-mails, and viruses. Many software companies offer free trial versions of network traffic monitors to promote their company.