B8ZS

B8ZS is an abbreviation for Bipolar with 8 Zeros Substitution (or Binary Eight Zero Substitution)- which is a method of line coding used in the T-carrier system which allows full 64 Kbits per second per channel, though it does not allow for Clear Channel Capability (CCC - 64 kbit/s.) in and of itself. The service would still have to be point-to-point (PTP) band not switched through a digital switching network. The standard is to use B8ZS as the line encoding option when providing PTP circuits and services. The older scheme was implemented in channel cards that always robbed a bit for signaling regardless if the service on that channel was switched or P2P. B8ZS cards can be optioned not to rob that bit.
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Abbreviation for bipolar with eight-zero substitution . A T-carrier line code in which bipolar violations are deliberately inserted if user data contains a string of 8 or more consecutive zeros. Note 1: B8ZS is used to ensure a sufficient number of transitions to maintain system synchronization when the user data stream contains an insufficient number of "ones" to do so. Note 2: B8ZS is used in the European hierarchy at the T1 rate.