The NetPebbles programming model is a natural fit to the systems management area. At present, system administrators routinely manage single systems using scripts written in Tcl, Perl, or Ksh. The NetPebbles paradigm extends the notion of scripting to the network. In a simple scenario, a system administrator would write a script to perform some management tasks on a set of machines. The tasks themselves are performed by components that are available on the network. The script specifies the interface supported by a component and optionally, the location of the component instance. It also specifies what methods to call on the component instances. The script visits each machine in the list, downloads (by runtime) relevant components from a central component repository and completes the task of management. The use of a scripting language simplifies programming. The ability to download components from a central code repository simplifies manageability of the components (equivalent to the management procedures under SNMP). The ability to move from one machine to another improves the scalability of the system.
In a more complex scenario, one can envision that the NetPebbles script could be programmed to perform application and machine specific tasks. To handle disconnection, one can envision a scenario where the script and related components are downloaded on the machine before the machine is disconnected. The script continues to perform system management tasks offline. When the machine reconnects later either via a dial-in or a LAN connection, the script can report back to the system administrator with the results. We are currently prototyping some of these ideas at IBM Research.