EXZ: Excessive Zeros
From Network Dictionary Wiki
Excessive Zeros (EXZ or EZ) is a type of error event in DS1(T1)/E1 and DS3(T3)/E3 interfaces when an AMI-coded signal is the occurrence of more than fifteen contiguous zeroes. For a B8ZS coded signal, the defect occurs when more than seven contiguous zeroes are detected.
There is only one source of this error: the customer. Excepting defective equipment, it indicates an improperly configured idle code. The default idle code is hex 7E, called "Seven Easy".
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