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doc/protocols.txt

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+Rosetta Operating System: Protocols
+===================================
+
+1 Introduction
+--------------
+
+   Due to its nature as a message-passing operating system, a standard
+   "langauge" is needed in order to allow different components of the system
+   to communicate with each other. This document describes the communication
+   layer built on top of kernel IPC primitives to facilitate the fast transfer
+   of structured data between components.
+
+
+2 Design Goals
+--------------
+
+   The key consideration for Protocols is low-overhead and speed. All system
+   functionality is accessed via sending messages, so any speed or memory costs
+   incurred will affect the performance of the entire system.
+
+   In addition, Protocols should be language-agnostic. Two components written
+   in two different programming languages should be able to communicate as long
+   as they both understand the same protocol.
+
+
+3 Overview
+----------
+
+   Protocols is a very thin layer overtop of Mango ports. It provides a
+   declarative language for describing message layouts in a language-agnostic
+   format, and a tool for generating concrete implementations of protocols in
+   various programming languages.
+
+   Protocols makes heavy use of Mango's I/O vectors facility to avoid performing
+   any dynamic memory allocation or unnecessary copying of data. As often as
+   possible, any parameters you pass to a protocol function will be copied
+   directly into the address space of the recipient. This makes Protocols
+   essentially free to use.
+