LysKOM can be seen as a cross between news and email, but with the presence and speed of IRC or ICQ. LysKOM is suitable for small or medium-sized communities. The largest known LysKOM server installation is used by slightly less than 1000 users each month, and typically has 300-500 simultaneous users.
LysKOM Protocol A is a protocol that runs on top of TCP/IP. It has been in use at Lysator since 1990, and has proven to be extensible in a backwards-compatible way. (Clients from dating from 1990 can still communicate with a modern server.) Since the start, it has used port 4894. That port was registered by IANA on 2001-06-20.
The LysKOM server and several clients are available for download from ftp://ftp.lysator.liu.se/pub/lyskom/ and http://www.lysator.liu.se/lyskom/.
| 11.1 (2003-08-30) | Texinfo | Info | Browsable HTML | Single-file HTML | DVI | |
| 11.0 (2003-08-24) | Texinfo | Info | Browsable HTML | Single-file HTML | DVI | |
| 10.7 (2002-11-03) | Texinfo | Info | Browsable HTML | Single-file HTML | DVI |
For even older versions, you have to check the server sources.