We have also added ad hoc comments on our experience with the different softwares and where possible links to brief case studies of use in the educational setting. There are numerous irc servers available and channel creation is easy. Communication is basic text with a variety of user commands to add depth. University firewalls can create problems. Telnet access is quick and easy.
Cores can be problematic to install but clients are extremely easy to instal.
University firewalls can be a problem. Internal commands offer initial hurdle but experience shows that they are easily acquired and indeed part of the satisfaction users enjoy. Telnet access is quick and easy.