In classifying such schemes, you need to consider several different
layers:
First, how is the information actually transmitted? For example, over
copper wire (what type of wiring, what voltage, what clock frequency,
etc.), over radio waves (what frequency? what power?), etc. How is
the signal encoded? Voltage versus a reference? Differential
voltage? Amplitude modulation? Frequency modulation? Embedded or
external clock?
How is the information encoded? What error correction or detection is
available? How are connections initiated and closed?
Once you have that, you need to layer a protocol such as SMTP, FTP,
etc. on top.
There are typically more layers than this in a network setup (via
satellite or otherwise), and this issue has been extensively studied.
Searching for "network layers" will bring up many documents talking
about the 7-layer model used to describe modern networks such as these
two:
Indiana University
http://www.uwsg.iu.edu/usail/network/nfs/layers.html
Boston University
http://cs-people.bu.edu/stevec/cs101/02s/network_layers.html
This is the sort of thing you will have to look for to understand and
discuss the various implementations satellite providers use.
Satellites themselves will only affect one or a few of these layers,
depending on the particular abstraction used. For example, TCP and
UDP don't care whether they are connecting through a satellite or over
CAT5e, whereas layer 1 is explicitly dealing with the satellites, and
layer 2 may need to be tailored for issues specific to high-latency
links such as provided by satellites.
Best of luck with your project!
-Haversian |
