At any moment, it is possible to list all Microcosm users that are able to cooperate. Having this information, a user can choose to open a talk session, inside the Microcosm environment, or send an email, or even start a whiteboard session. Currently there are a number of sophisticated tools on the market that could be integrated with Microcosm to support the exchange of ideas between users. For reasons of economy we concentrated our attention on the public domain packages. For the whiteboard we choose wscrawl (ftp dizzy.cv.hp.com) [6, 16], although a more modern tool, like Collage [17], might provide more functionality. Besides being a whiteboard application, wscrawl also allows users to have loosely coupled sessions (each user has their own screen cursor), and tightly coupled session (users share a telepointer). SEPIA, mentioned previously, is another cooperative hypermedia system that also uses wscrawl as a whiteboard interface. A very interesting discussion about loosely and tightly coupled sessions, and a comparison between hypermedia systems that integrate CSCW mechanism can be found in [18, 19, 20]. We also implemented a protocol to deal with all the requests. The protocol to establish a whiteboard session, for example, consists of:
For the whiteboard we add awareness information such as: which sessions are active, participants of sessions, facilities to allow a new session to start, insertion of a person in a session, request to join a specific session. In all cases a similar protocol applies. Figure 3 shows one of the dialog boxes used to implement this protocol.
Figure 3: Cooperative Protocol
The cooperative server is where all the information is concentrated. Every time that a new user is added to a session, the server broadcasts this information to all others participants, so updated information can be visualised on their screen. Users that are not participants of a session can also request awareness information from the server. Figure 4, shows a whiteboard session and some of the awareness information available. Users in a session can also activate a special method for following links: cooperative follow link. In this mode, any link followed by one participant will be followed by all others users in the session that has this option set on. When a link has more than one destination, all destinations are presented to all participants, and a discussion dialog box appears to give users the opportunity to agree about which destination is the most appropriate to be followed. This kind of discussion can be very constructive in an interactive learning environment, stimulating students to argue and give arguments for their positions. As a commercial application we could suggest the use of this functionality for maintenance. A technician considering a fault could contact an expert in the office and both having the details of the problem to be solved on their screen could follow links together to more detailed information in order to find the fault and then follow new links to find best way to fix the fault. A very promising and interesting project of this type is being undertaken at Southampton in collaboration with Pirelli Cables UK LTD [21, 22]. The architecture of the system also allows notification to all other participants of new links created. In a conference, for instance, it would allow buttons to be shown to all participants on the fly, linking to some background information owned by one of the participants.
Figure 4: Example of awareness information