×

Conflict resolution by retransmission delay on shared communication medium

  • US 4,234,952 A
  • Filed: 06/07/1979
  • Issued: 11/18/1980
  • Est. Priority Date: 06/07/1979
  • Status: Expired due to Term
First Claim
Patent Images

1. A data communication modem adapted for use in conjunction with a plurality of other modems over a shared communication medium, said modem comprising:

  • a transmitting and receiving means for transmitting and receiving data over the communication medium;

    a first sense means coupled to said modem for detecting carrier transmission from any of the modems on the communication medium (busy) and for detecting no transmission (idle) on the communication medium;

    a second sense means for detecting simultaneous transmission (interference) of more than one modem;

    a computation means for determining a first duration of time between the time of transition from an idle channel to a busy channel and the time of transmission interference, and a second duration of time between the time of transmission interference and the time of transition from a busy channel to an idle channel; and

    a control means responsive to outputs from said first sense means, said second sense means and said computation means for governing transmission of said modem so that said modem will not transmit until said first sense means is not detecting carrier transmission and will interrupt transmission if interference is detected by said second sense means.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×