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X-WR-CALDESC:22 July 1919: On this day in 1919\, Gilbert Vernam patented hi
 s Secret Signaling System\, marking a milestone in communication technolog
 y! He later secured a whopping 65 patents in this field. His 'Secret Signa
 ling System' describes an automated teletype cipher. \n\nIn this automated
  system\, a loop of perforated paper tape representing random letters was 
 added to a plaintext message to create the ciphertext. On the receiving en
 d\, a duplicate loop would be used to subtract the same random letters fro
 m the ciphertext to re-create the plaintext message. The advantage was the
  encipherment and decipherment was handled automatically without human int
 ervention or error. The use of a loop of tape meant the system was not tru
 ly a one-time pad since the key tape would be reused\, so it was vulnerabl
 e to enemy decryption. (Excerpted from ciphermachines.com) \n\nThe US mili
 tary SIGTOT teletype system was the first use of an automated one-time tap
 e\, used by the US military. It was introduced in 1925 and was the 'Secret
  Signaling System' directly based on Vernam's 1919 patent. It remained in 
 use by the US military until the 1959. In the photo is a Special Transmitt
 er/Distributor for the US military SIGTOT teletype cipher. The one picture
 d here was used in President Roosevelt's airplane and is now at the NCM.\n
 \nGilbert Vernam was an inventor who held 65 patents in the field of commu
 nication. He made significant contributions to the science of cryptography
 \, and to the present-day\, world-wide telegraph communications systems.\n
 \nLearn more via the link below to Vernam’s paper\, “Cipher Printing Teleg
 raph Systems.”
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DTSTART:20251102T020000
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
RDATE:20261101T020000
RDATE:20271107T020000
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DTSTART:20260308T020000
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RDATE:20270314T020000
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BEGIN:VEVENT
UID:360c36c7-507a-45f0-bf7a-1213e6feedd9
DTSTAMP:20260424T093933Z
DESCRIPTION:22 July 1919: On this day in 1919\, Gilbert Vernam patented his
  Secret Signaling System\, marking a milestone in communication technology
 ! He later secured a whopping 65 patents in this field. His 'Secret Signal
 ing System' describes an automated teletype cipher. \n\nIn this automated 
 system\, a loop of perforated paper tape representing random letters was a
 dded to a plaintext message to create the ciphertext. On the receiving end
 \, a duplicate loop would be used to subtract the same random letters from
  the ciphertext to re-create the plaintext message. The advantage was the 
 encipherment and decipherment was handled automatically without human inte
 rvention or error. The use of a loop of tape meant the system was not trul
 y a one-time pad since the key tape would be reused\, so it was vulnerable
  to enemy decryption. (Excerpted from ciphermachines.com) \n\nThe US milit
 ary SIGTOT teletype system was the first use of an automated one-time tape
 \, used by the US military. It was introduced in 1925 and was the 'Secret 
 Signaling System' directly based on Vernam's 1919 patent. It remained in u
 se by the US military until the 1959. In the photo is a Special Transmitte
 r/Distributor for the US military SIGTOT teletype cipher. The one pictured
  here was used in President Roosevelt's airplane and is now at the NCM.\n
 \nGilbert Vernam was an inventor who held 65 patents in the field of commu
 nication. He made significant contributions to the science of cryptography
 \, and to the present-day\, world-wide telegraph communications systems.\n
 \nLearn more via the link below to Vernam’s paper\, “Cipher Printing Teleg
 raph Systems.”
DTSTART;TZID=America/New_York:20260722T060000
DTEND;TZID=America/New_York:20260722T060001
LOCATION:
SUMMARY:1919: Patent issued to Gilbert Vernam for concept of machine enciph
 erment.
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