INLS 187

1
INLS 187

• November 4, 2004
• Telecom Hacking

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A few words about telecom hacking so I can say I
covered it

• Hacking phone systems is known as phreaking
• Peopl are phreaks or phreakers
• In the 1970s early 1980s, phreaking was
  extremely popular
• 2600 Phrack magazine covered the phreaking set

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Objective

• The objective of most phone phreaks was to get
  free phone calls, especially long distance
• Playing with the system was an electronic form of
  urban explorationforbidden fruit
• People like Mitnick, Steve Wozniak, Steve Jobs,
  Kevin Poulsen, Mark Abene, Evan Doorbell, etc.
  did it for thrills

4
Technology

• Switchboard operators were replaced by
  electromechanical switching systems in the 1940s
  and 1950s
• The Crossbar system used line voltages for tones,
  dialing, and ringing the handset (LTE)
• Dialing resulted in a series of pulses
• The "user had hung up" tone was 2600 Hz. When the
  system detected that tone, it hung up the phone,
  thinking the call was ended.

5
The Phreak Legend

• one day a blind student was playing with the
  phones in his local university when he whistled
  into it, and the phone suddenly hung up.
• After some experimentation and a few calls to
  local technicians, he learned that he had
  stumbled across the "user had hung up" tone,
  2600 Hz.
• Probably more likely that someone just got it
  from a telco employee or a manual.

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Technology

• The trick was to call a toll free number or
  long-distance directory number and then play the
  2600 Hz tone into the line before the call was
  answered on the other side of the line. Then you
  could dial the number you actually wanted on a
  blue box, and the remote crossbar would connect
  you for free.

7
Technology

• phreaks knew that a true solution would be
  impossible because it would require adding filter
  hardware to every line on every crossbar in the
  world. Unless the phone company replaced all
  their hardware, phreaking would be impossible to
  stop.
• By the 1980s, computerized switches had replaced
  all the old crossbar switches in the USAstill
  lots overseas though
• Computerized systems opened up all new avenues of
  remote intrusion

8
Boxing

• Telecom terminology refers to any kind of device
  as a box
• Phreakers adopted this term and use different
  colors to denote different type bloxesblue,
  black, red, beige, clear, etc. Around 100 in all.

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Captain Crunch

• The most famous phreaker is John Draper, a.k.a.
  Captain Crunch.  In the 1960s, he found a free
  whistle enclosed in each box of Captain Crunch
  cereal which, when held and whistled into a
  telephone handset, made the exact same sound as
  the telephone switching equipment.  This whistle,
  with years of practice and one hole glued shut,
  could open telephone lines by blowing a precise
  tone into a pay telephone and make it possible to
  conduct free long-distance calls.  He used his
  talents to call home for free when he was
  stationed in England with the US Air Force. 

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Draper, cont.

• Draper is also credited with inventing the blue
  box. 
• Captain Crunch soon became famous and even stated
  that he eavesdropped on telephone conversations
  by the President of the US and the FBI 
• Eventually, his techniques became obvious to the
  various phone companies and he was caught and
  faced three separate convictions. 
• The most severe sentence he received was one year
  in a county jail.

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Yippies

• In 1971, some hippies discovered the possibility
  of making free calls. A faction of the hippie
  movement, known as "yippies" , started a magazine
  called Youth International Party Line (Youth
  International Party being the groups formal
  name). The paper's mission was to teach methods
  of telephone fraud. Prominent yippies (whilst
  never referring to themselves as the 'leaders')
  were Abbie Hoffman and Jerry Rubin.

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Today

• With the breakup of Ma Bell, phreakers have a
  whole new universe of companies and technologies
  to play with
• Cellular telephony
• Private PBX systems
• Voice mail systems
• Calling cards
• VoIP
• WiFi

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More

• Caller ID
• Party lines
• Exploits
• Alberta Termination Test Line
• Quiet Termination
• Loop line
• Ringback
• ANAC

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Criminal Element

• There has always been an underworld element
  interested in telephony, money can be made
  stealing long distance services
• Drug dealers want stolen cell phones and voice
  mail boxes

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Conclusion

• Phone phreaks were some of the original hackers
• As technologies merge, there will undoubtedly be
  new and interesting things for phreaks to play
  with
• Stakes are higher nowgovernments want to
  prosecute like never before!