Nowadays the Internet infrastructure is so pervasive that it is common that people connect their laptop computer from a range of different locations: office, home, the hotel hosting them for a conference, or the meeting room where they are working. This is sometimes called mobile computing and it forces the designers of applications to cope with two new requirements: (1) users may connect to the network from arbitrary locations (usually with different network addresses) , and (2) they are not permanently connected. Thus, connectivity is intrinsically transient, and machine disconnection is not an exceptional case, but the normal way of operating. We investigated how collaborative work can be supported in a mobile computing setting, where the notion of permanent central server cannot be used. Support tools for CSCW are normally based on a client-server architecture, which appears to be unsuitable in a such a dynamic environment. For this reason we experimented peer-to-peer solutions, which do not rely on services provided by a centralized server. In particular, we have implemented a configuration management tool -- called PeerVerSy -- which provide collaborative actions even when some of the collaborating nodes are off-line
