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Minor correction.
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edit approved May 8, 2023 at 18:16
Chan Tai Man
edit approved May 8, 2023 at 18:16
Chan Tai Man
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In this case there is simply not enough information to make a determination.

The Ringstellung for the middle rotor only comes into play every 26x26=67625x26=650 steps. A message of length 174 characters only sees 174/26=6 or 7 turnovers and so only allows us to test six or seven possible Ringstellungen (in this case -7,...,-13) all of which do not give a readable message in this case. To be sure of being able to test all 26 possible middle Ringstellungen, we'd need a message of 676650 characters. If we do not witness a turnover in the second rotor, we certainly do not see one in the third and so the slow Ringstellung requires even more data (1757616,900 characters to be sure of witnessing a slow turnover).

At Bletchley Park, once almost all of the settings have been recovered as in your attack, other messages would become very easy to attack and so looking at a longer message would help recover the middle Ringstellung (or several shorter messages would allow other possible Ringstellung values to be eliminated). Remember that Bletchley were processing thousands of Enigma messages each day, so using multiple messages was more than feasible.

In this case there is simply not enough information to make a determination.

The Ringstellung for the middle rotor only comes into play every 26x26=676 steps. A message of length 174 characters only sees 174/26=6 or 7 turnovers and so only allows us to test six or seven possible Ringstellungen (in this case -7,...,-13) all of which do not give a readable message in this case. To be sure of being able to test all 26 possible middle Ringstellungen, we'd need a message of 676 characters. If we do not witness a turnover in the second rotor, we certainly do not see one in the third and so the slow Ringstellung requires even more data (17576 characters to be sure of witnessing a slow turnover).

At Bletchley Park, once almost all of the settings have been recovered as in your attack, other messages would become very easy to attack and so looking at a longer message would help recover the middle Ringstellung (or several shorter messages would allow other possible Ringstellung values to be eliminated). Remember that Bletchley were processing thousands of Enigma messages each day, so using multiple messages was more than feasible.

In this case there is simply not enough information to make a determination.

The Ringstellung for the middle rotor only comes into play every 25x26=650 steps. A message of length 174 characters only sees 174/26=6 or 7 turnovers and so only allows us to test six or seven possible Ringstellungen (in this case -7,...,-13) all of which do not give a readable message in this case. To be sure of being able to test all 26 possible middle Ringstellungen, we'd need a message of 650 characters. If we do not witness a turnover in the second rotor, we certainly do not see one in the third and so the slow Ringstellung requires even more data (16,900 characters to be sure of witnessing a slow turnover).

At Bletchley Park, once almost all of the settings have been recovered as in your attack, other messages would become very easy to attack and so looking at a longer message would help recover the middle Ringstellung (or several shorter messages would allow other possible Ringstellung values to be eliminated). Remember that Bletchley were processing thousands of Enigma messages each day, so using multiple messages was more than feasible.

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Daniel S
Daniel S
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In this case there is simply not enough information to make a determination.

The Ringstellung for the middle rotor only comes into play every 26x26=676 steps. A message of length 174 characters only sees 174/26=6 or 7 turnovers and so only allows us to test six or seven possible Ringstellungen (in this case -7,...,-13) all of which do not give a readable message in this case. To be sure of being able to test all 26 possible middle Ringstellungen, we'd need a message of 676 characters. If we do not witness a turnover in the second rotor, we certainly do not see one in the third and so the slow Ringstellung requires even more data (17576 characters to be sure of witnessing a slow turnover).

At Bletchley Park, once almost all of the settings have been recovered as in your attack, other messages would become very easy to attack and so looking at a longer message would help recover the middle Ringstellung (or several shorter messages would allow other possible Ringstellung values to be eliminated). Remember that Bletchley were processing thousands of Enigma messages each day, so using multiple messages was more than feasible.