A network device includes a communication interface and a transmitter coupled to the communication interface. The transmitter is configured to determine to start an auto-negotiation page with a link partner, and transmit, through the communication interface, a start delimiter for the auto-negotiation page. The transmitter transmits the start delimiter by transmitting a first pulse comprising a first encoding violation, followed by a second pulse comprising a second encoding violation. The transmitter may shorten the first pulse and the second pulse relative to a different pre-defined start delimiter to define spectral content for the first pulse and the second pulse that passes different first and second receiver filters in the link partner for different first and second communication standards.