This attribute defines the zero encoding on the DS1 line.
bit7Stuffing sets bit 7 of every timeslot to a one to guarantee ones's
density. This reduces the available bandwidth of the channel by 1/8.
b8zs substitutes a pattern of bipolar violations if more than 7 zeros
in a row are to be transported.
ami specifies Alternate Mark Inversion, in which successive marks
(ones) alternate between positive and negative polarity voltage
signals, and spaces (zeros) are sent as a zero amplitude signal.
When zeroCoding is set to ami and lineType is set to d4, it is
recommended that raiAlarmType be set to SBit in order to avoid
possible mimic RAI alarm.
For cell-based cards only the default value b8zs is permitted.