The basic requirements for the World Wide Laboratory in either the service, collaboration or education modes are relatively straightforward. On the user end we need a network connection and a standard web browser. On the instrument end we need a network connection and interface software to interpret the commands coming in over the network.
There are several advantages to using a web browser interface. First, almost everyone knows how to use a web browser and there is no need for training on a specific user interface. Second, web browsers are now ubiquitous on all computer systems and third there are no special software or hardware requirements. As a result, we can be reasonably sure that a remote user anywhere in the world with access to the Internet will have the tools to run the instruments remotely.
There are other remote user interfaces that use techniques such as remote screen copy (for example Timbuktu) or low level distributed windowing libraries such as X-windows. All of these systems require specialized software to be installed and maintained on the remote user's computer system.
From our experience with the World Wide Laboratory there are at least three instrument access modes that need to be supported. These are:
Single User: Allows dedicated access to an imaging system by a single user.
Multiple non-cooperating users: Allow several users to access the system simultaneously. The users are not aware of each other. Commands from the users are queued and the data is returned to the requesting user. This mode is useful in education projects like Chickscope where several classrooms may be accessing the instrumentation simultaneously.
Multiple cooperating users: Allows several users to use an instrument collaboratively by using mechanisms for passing instrument control among the users.