LAN messenger

A LAN messenger is an instant messaging program designed for use within a single local area network (LAN).

There are advantages using a LAN messenger over a normal instant messenger. The LAN messenger runs inside a company or private LAN, and so an active Internet connection or a central server is not required (P2P). Only people who are inside the firewall will have access to the system. Communication data does not leave the LAN, and also the system can not be spammed from the outside (Darknet). Many LAN messenger offer basic functionality for sending private messages, file transfer, chatrooms and graphical smileys.

History

On Unix there is the command talk which enables users to directly talk with each other, first versions were available on a DEC PDP-11 computer system in the 1970s. The used NTALK-protocol has also been used by programs on other operating systems, for example TalkR and WinTalk on Windows. With the spreading of Samba it became possible to send text messages in heterogeneous networks (smbclient). Nearly all Linux distributions offer a samba package.

The first LAN messenger for Windows is WinPopup, a small utility included since Windows 3.11. WinPopup uses SMB/NetBIOS protocol and was intended to receive and send short text messages. Windows NT/2000/XP improves upon this with Messenger service, a Windows service compatible to WinPopup. On systems where this service is running, the received messages "pop up" as simple message boxes. Any software compatible with WinPopup, like the console utility NET SEND, can send such messages. By default, messenger service is off in Windows XP SP2 and blocked by Windows XP's firewall.

With Apple's Bonjour protocol messages can be exchanged in the LAN without a central server, it was introduced in Mac OS X in 2005. The multi-protocol messenger Pidgin has support for the Bonjour protocol.

See also

• Comparison of LAN messengers
• Friend-to-friend
• Messenger service
• Talker