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There are two distinct categories of autonomy. One category reflects local system autonomy. The other category reflects the autonomy associated with the core infrastructure distributed services that form the heart of a distributed system.

Each local system, in a distributed system, is highly autonomous. They may have entirely different policies and usage from the whole, can decide to which extent they wish to share, and may join and depart, at will, from the distributed system.

However, once a local system decides to enter the distributed system, it is bound to a set of contracts governing behavior, communications, and interfaces. By following the contracts, the local system can then use the services provided or even provide services itself.

The systems that materialize the core infrastructure services have more restrictions on their autonomy. They must have consistent, well-defined communication protocols and follow all contracts. Even though they are managed independently of the local systems, they are bound by a contract to provide a certain level of expected service.

Ronald LeRoi Burback