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[[!meta copyright="Copyright © 2007, 2008 Free Software Foundation, Inc."]]

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IPC stands for interprocess communication.

On [[Unix]], interprocess communication can be achieved using pipes.
This is inefficient for large amounts of data as the data must be
copied.  This is generally not a problem as most services are
provided by the Unix kernel and Unix is not designed to be
[[extensible|extensibility]].

[[Microkernel]] systems, on the other hand, are generally composed
of many components.  As components are separated by their respective
[[address_space]] boundaries, unlike the kernel, they cannot arbitrarily
examine and modify the caller's state.  The advantage is that if the
protocol is carefully designed, the callee cannot cause the caller
any [[destructive_interference]] thereby removing the need for the
caller to [[trust]] the callee thus reducing the former's [[tcb]].
When done systematically, this can increase the system's [[robustness]].
To this end, microkernels provide richer IPC semantics that include
the ability to transfer [[capabilities|capability]] and to use [[virtual_memory]]
[[mechanism]]s to copy data.


# See Also

* [[RPC]]