Preface The expedition ARK XIX/3 with the German icebreaking RV ...

Satellite
Internet
Satellite dish
AWI
Fig. A4.10-2: Actual Network Setup.
Test and Results
A series of 64 bytes packets were sent to the AWI internet protocol (IP) address in
Bremerhaven in order to test the round trip time (RTT) from the RV "Polarstern"
research vessel to Bremerhaven and back. The test will also determine the reliability
of the satellite link and can also be used as an initial rough guide to the speed of the
transmission. The result will not determine the exact speed of the transmission due to
the asymmetry in satellite communication links.
The results obtained for the tests showed a RTT of an average of 753 ms with a
minimum 753 ms and a maximum time of 758 ms. This worked out at around 680 bps
transmission speed, a very slow speed. The results do not concur with the results of
earlier tests, therefore further testing are required.
The success rate for the tests was only 43 %, verifying the general acceptance that
satellite links are unreliable. However, further tests are again required in different
conditions as there are too many factors that may cause a data packet to be dropped.
Conclusion
The tests performed on this expedition have shown that the constraints to the final
objective of this project will be the speed and the reliability of the satellite link. These
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