"Host Processor"
The central computer in a hierarchical distributed processing system, which is typically located at some central site where it serves as a focal point for the collection of data, and often for the provision of services which cannot economically be distributed.
Is this what you mean by Host Processor?
If some other computer shuts down you have no need to fix your machine - somebody needs to fix the host machine - what services is it providing for you?
Peccavi, May 2010