Telephone transmission system, telephone transmission server and display unit

A telephone transmission server, comprising:

• a clock tracking a clock time;
• a unit information memory storing a unique ID of a display unit and a telephone number associated with the display unit;
• a receiver receiving information generated by an operation of a telephone;
• a pseudo-random number generator generating, when the receiver receives the information, a pseudo-random number from the clock time tracked by the clock and the unique ID stored in the unit information memory;
• a determiner using the clock time and the unique ID stored in the unit information memory to make a determination of whether or not the information indicates the pseudo-random number;
• a determiner making a matching determination to find a match between the information and the pseudo-random number;
• and
• a communication controller connecting the telephone to the telephone number associated with the display unit when the matching determination is successful.

A display unit constituting a telephone transmission system in combination with a telephone transmission server, comprising:

• a first clock tracking a first clock time;
• a unique ID memory storing a unique ID;
• a first pseudo-random number generator generating a first pseudo-random number from the unique ID and the first clock time tracked by the first clock;
• and
• a display displaying the first pseudo-random number, wherein
• the telephone transfer server includes:
• a second clock tracking a second clock time;
• a unit information memory storing the unique ID of the display unit and a telephone number associated with the display unit;
• a receiver receiving information generated by an operation of a telephone;
• a second pseudo-random number generator generating, when the receiver receives the information, a second pseudo-random number from the second clock time tracked by the second clock and the unique ID stored in the unit information memory;
• a determiner making a matching determination to find a match between the information and the second pseudo-random number;
• and
• a communication controller connecting the telephone to the telephone number associated with the display unit when the matching determination is successful.