Abstract: A multi-processor, multi-tasking virtual machine comprises processes, messages, and contexts. Processes communicate only through messages. Contexts are groups of related processes.The virtual machine makes all hardware devices appear to be processes, in that the occurrence of an event on a device causes a message to be generated and sent to another process for handling. The receiving process performs all operations required to handle the event. Thus a variety of hardware devices can be connected and disconnected from the system without interrupting its operation and without necessitating extensive software revisions.

Abstract: A multi-processor, multi-tasking virtual machine comprises processes, messages, and contexts. Processes communicate only through messages. Contexts are groups of related processes. The virtual machine is implemented in a distributed data processing system comprising a plurality of individual cells coupled by a local area network (LAN). Each cell may comprise one or more processes and/or contexts.A network interface module (NIM) provides the interface between any individual cell and the LAN. To facilitate message transmission between processes resident on different cells, each NIM is provided with tables identifying the locations of resident and non-resident processes, respectively. Cells may be added to or deleted from the LAN without disrupting the LAN operations.

Abstract: A multi-processor, multi-tasking virtual machine comprises processes, messages, and contexts. Processes communicate only through messages. Contexts are groups of related processes. The virtual machine is implemented in a distributed data processing system comprising a plurality of individual cells coupled by a local area network (LAN). Each cell may comprise one or more processes and/or contexts.A network interface module (NIM) provides the interface between any individual cell and the LAN. To facilitate message transmission between processes resident on different cells, each NIM provides addressing modes allowing messages to be sent to processes according to the processes' names. Cells may be added to or deleted from the LAN, and processes may be created or deleted, without disrupting the LAN operations.