def get_pause_time(self, speed=ETHER_SPEED_MBIT_1000):
        """
        get pause time for given link speed in seconds

        :param speed: select link speed to get the pause time for, must be ETHER_SPEED_MBIT_[10,100,1000]  # noqa: E501
        :return: pause time in seconds
        :raises MACControlInvalidSpeedException: on invalid speed selector
        """

        try:
            return self.pause_time * {
                ETHER_SPEED_MBIT_10: (0.0000001 * 512),
                ETHER_SPEED_MBIT_100: (0.00000001 * 512),
                ETHER_SPEED_MBIT_1000: (0.000000001 * 512 * 2)
            }[speed]
        except KeyError:
            raise MACControlInvalidSpeedException('Invalid speed selector given. '  # noqa: E501
                                                  'Must be one of ETHER_SPEED_MBIT_[10,100,1000]')
get pause time for given link speed in seconds

        :param speed: select link speed to get the pause time for, must be ETHER_SPEED_MBIT_[10,100,1000]  # noqa: E501
        :return: pause time in seconds
        :raises MACControlInvalidSpeedException: on invalid speed selector