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+========
+Ethernet
+========
+
+.. warning:: Under progress!
+
+History
+=======
+Bob Metcalfe first described the ethernet system in a memo while working at
+the Xerox Palo Alto Research Center in 1973 ([oreilly]_). It was based on
+the earlier *Aloha* system developed by Norman Abramson at the University of
+Hawaii. *Aloha* was a radio network for inter-island communications.
+
+Structure
+=========
+
+Data Frames
+~~~~~~~~~~~
+The frame format is the same for ethernet systems of any speed.
+
+====================       ===========
+Section                    Size (bits)
+====================       ===========
+Preamble                   64
+Destination Address        48
+Source Address             48
+Type Length                16
+Data                       46 to 1500
+Checksum                   32
+====================       ===========
+
+.. topic:: Preamble
+
+    The preamble originally served as a "warm up" period for hardware to 
+    stabilize and prepare for the rest of the frame.
+
+.. topic:: Source and Destination addresses
+
+    Manufacturers are given a 24 bit id (first half), and are expected to
+    ensure the uniqueness of the second half of each device's address.
+
+    The IEEE-SA (Standards Association) delegates addresses.
+
+.. topic:: Checksum
+
+    The checksum (or Frame Check Sequence) is a Cyclic Redundancy Checksum.
+
+.. [oreilly] `Ethernet: The Definitive Guide`:title:, by Charles Spurgeon.
+              O'Reilly, 2000