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ALOHANET
packet radio network (developed
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by
the University of Hawaii in 1971 to provide
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terminal
access to a central computer)
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popularized
random access protocols.
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Two
9600 bps channels: inbound and outbound.
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The
inbound channel uses a MAC protocol
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known
as (pure) ALOHA:
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stations
transmit packets whenever they have data to
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sent
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inbound
packets are ACKed. If no ACK is received
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during
a random timeout interval, the packet is
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retransmitted
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Pure
ALOHA is basis for many other MAC
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protocols,
including Ethernet
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Works
well under light load, under heavy load,
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channel
utilization is only 18%
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