A LAN Messenger is a chat system that provides news on the local network (LAN). Two or more users can chat via text messages. Users need to be interconnected with a computer program, the data transfer will take place on the local network, an Internet connection or a central server are not necessary (P2P ). This LAN messenger are especially suitable for home networks. The following basic functions are offered by LAN messengers typically: Send private messages, send files, chat rooms and graphical smileys.

The use of a LAN messenger instead of a normal instant messenger brings certain advantages. For example, a LAN Messenger is running within a corporate or private network, so people can only access inside the firewall on the system. The data communication does not leave the local network ( can not be heard) and also can not be spammed from the outside ( darknet ).


On Unix, there is the talk command with the logged-in user can directly get in touch, the first version there was on DEC PDP -11 computer systems since the 1970s. The case used Ntalk protocol also used programs on other operating systems, such as TalkR and WinTalk under Windows. With the proliferation of Samba, it was also possible to exchange text messages in heterogeneous networks, almost all Linux distributions now include Samba packages.

The first LAN Messenger for Microsoft Windows is WinPopup (based on the SMB / NetBIOS protocol). WinPopup is a simple utility that already exists since Windows 3.11 and can send short text messages. Messages appear to the recipient as a pop-up window ( for example, was used in the 1990s as a notification). Since Windows NT has its own messenger service that is compatible with WinPopup. Since the introduction of Service Pack 2 for Windows XP, this service is disabled by default.

With Apple's Bonjour protocol can exchange messages in the LAN, it was introduced in Mac OS X in 2005. Among other things, supports the multi- protocol messenger Pidgin since 2007 the Bonjour protocol.