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The model

The basic idea of the DSM is to treat each device as an object which is created and stored in a process called a server. Each device is a separate entity which has its own data and behaviour. Each device has a unique name which identifies it in network name space. Devices are configured via resources which are stored in a database. Devices are organised according to classes, each device belonging to a class. Classes are implemented in C using a technique called Objects In C. All classes are derived from one root class. The class contains a generic description of the device i.e. what actions can be performed on the device and how to implement them. The actions are available via commands. Commands can be executed locally i.e. in the same process, or remotely i.e. across the network. Network access is implemented using a remote procedure call which is accessed via an application programmers interface.



Andy Goetz
Tue Jan 28 13:58:13 MET 1997