When you are dealing with a satellite network you have so many variables to overcome it is amazing that it works at all.
Satellite networks have always posed a problem to network designers; the limited bandwidth
available on the satellite and the high-latency of the round trip of a signal between the satellite hub,
the satellite and the satellite service subscriber impose restrictions on what types of information can
be transmitted.
Communications over geo-synchronous satellites, orbiting at an altitude of 22,300 miles, have
round-trip times of approximately 540 ms, an order of magnitude greater than most terrestrial
networks. This long trip through the atmosphere also introduces a much higher bit error rate than
terrestrial connections. Most of us are familiar with the annoying latency in a satellite voice
connection, and this latency creates a comparatively complicated problem in the transmission of
TCP/IP.
TCP or Transmission Control Protocol is used to create reliable IP sessions between a sending and
a receiving IP addresses. It was originally designed to run on low latency local area networks, and
each packet is acknowledged after it is sent. This makes TCP a very “talky” protocol, and uses up a
great deal of the limited bandwidth available on the satellite link, reducing the efficiency of the
connection.
http://www.encorenetworks.com/documents/wp_encore_satellite_vpns.pdf
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