B8ZS

Glossary

BB8ZS

See Bipolar 8 Zero Substitution (B8ZS).

Basic Rate Interface (BRI)

A standard ISDN frame format that specifies the protocol used between two or more communications systems. As used in North America, BRI provides 23

64-kbps B-channels (voice or data) and one 64-kbps D-channel (signaling). The D-channel is the 24th channel of the interface and contains multiplexed signaling information for the other 23 channels.

bandwidth

The amount of data that a given channel can transmit in a given period of time, measured in bits per second (not bytes per second) on digital networks or in Hertz (cycles per second) on analog networks. For analog transmission, the

band width can be measured as the difference, expressed in hertz, between the highest and lowest frequencies transmitted.

baud

A unit of transmission rate equal to the number of signal events per second. See also bit rate.

BCC

See bearer capability class (BCC)

bearer capability class (BCC)

Code that identifies the type of a call (for example, voice and different types of data). Determination of BCC is based on the caller’s characteristics for non-ISDN endpoints and on the Bearer Capability and Low-Layer Compatibility Information Elements of an ISDN endpoint. Current BCCs are 0 (voice-grade data and voice), 1 (DMI mode 1, 56 kbps data transmission), 2 (DMI mode 2, synchronous/asynchronous data transmission up to 19.2 kbps) 3 (DMI mode 3, 64 kbps circuit/packet data transmission), 4 (DMI mode 0, 64 kbps synchronous data), 5 (temporary signaling connection, and 6 (wideband call, 128–1984 kbps synchronous data).

BER

Bit error rate.

Bipolar 8 Zero Substitution (B8ZS)

B8ZS line coding substitutes a mix of 1s and 0s for every group of eight consecutive 0s in a stream of AMI-encoded data (see line coding). The encoded string contains consecutive ones with the same polarity. These intentional, bipolar violations of the AMI coding scheme let the receiving end identify, decode, and restore the long zero strings in the original message. B8ZS line coding does not corrupt digital data, so it is commonly used with T-1lines.

Administration for Network Connectivity

 

 

555-233-504 — Issue 1 — April 2000

CID: 77730

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Lucent Technologies Release 8.2 manual BB8ZS, Bcc, Ber