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BBS's versus DIGIPEATERS in space



Compared to the fun we are having with communicating with UI frames via 
MIR in this country, someone just sent me a copy of a MIR pass in Europe.
What a waste of bandwidth! I analyzed all 350 packets and here are the
statistics broken down into the successful TEXT packets in 3 categories:

BBS:   330 packets to transfer 27 useful lines of text = 8%   effeciency
CNCT:   17 packets to transfer  1 useful line  of text = 6%   effeciency
UI:      2 packets to transfer  2 useful lines of text = 100% effeciency

The two UI stations communicated perfectly in 2 packets
The two CONNECTED stations communicated 1 line only 1 way with 17 packets
31 of the 33 stations attempting to connect to the BBS accomplished
      nothing!  And still spent 280 packets doing it!

BBS'S ARE NOT THE WAY TO USE PACKET RADIO ON SATELLITES!

You may argue that the BBS is for the crew.  EVEN SO, with the right
software (APRS), these same 350 packets could have exchanged 350 lines
of text traffic to and from the crew or anyone else if they had only used
UI packets!

Here are the details if you are interesetd:

350  TOTAL BBS RELATED PACKETS AS FOLLOWS (2 users got logged on):
     280  DISCONNECT-BUSY packets  150 from just 6 stations!
      30  Lines of BBS overhead LINES (welcome, command prompts, etc)
      20  Acks and RETRIES and CHECKS
      17  lines of HEARD LOG 
      10  message headers listed (at least 2 times each)
       0  messages read  (ZERO)

 17  STATION-TO-STATION REQ/and RETRIES to convey only ONE LINE!
       1  message line conveyed

  2  APRS TYPE Position/STATUS packets conveying station position and
       status

CONCLUSION:  If we designed Amateur Satellites to be dumb digipeaters for
UI frames only, then every successful packet CONTAINS USEFUL INFORMATION.
In this case there would have been 350 lines of data, not just 29.

de WB4APR, Bob


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