Ethernet: Control Procedures

• defer - do not transmit if:

  • carrier present (manchester transitions)
  • within minimum spacing at end of frame

• transmit - if not deferring

  • transmit until completed or collision detected

• abort - if collision detected:

  • stop transmission
  • jam (4-6 bytes) to insure all stations detect

• retransmit - if collision detected:

  • wait random time - backoff algorithm

    • eg double delay with repeated collisions

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