12
APPENDIXES
12.1 ACRONYMS AND DEFINITIONS
Some terms are defined at the locations referenced in the Index.
0x | Indication that the following characters are a hexadecimal expression. |
5ESS | Class 5 Electronic Switching System, CO voice switch that serves end users. |
AB | Two signaling bits in T-1 CAS when using a superframe. |
ABCD | Four signaling bits in T-1 CAS when using the extended superframe. |
ABNF | Augmented Backus—Naur Form. |
AC | Area Code, in telephone number. |
ACD | Automatic Call Distributor, PBX function or machine to spread calls among phones. |
ACELP | Adaptive CELP. |
ACF | Admission Confirm. |
ACK | ACKnowledge, message type to confirm receipt of request or action taken. |
ADC | Analog-to-Digital Converter, first step to encode voice as a digital stream. |
address | IP address of a host; MAC, DLCI, or other L2 destination or source identifier; cf socket. |
ADPCM | Adaptive Differential Pulse Code Modulation, form of compressed voice encoding. |
AH | Authentication Header, form of IPsec that digitally signs but doesn't encrypt. |
A-Law | Form of PCM companding used with E-1 links. |
ALF | Application Level Framing. |
ALG | Application Layer Gateway. |
ALI | Automatic Location Information (Identifier), geographic indication associated with a telephone, landline or cellular, delivered to a PSAP with E911 call; kept in an ALI database. |
AN | Acknowledgment Number, associated with an octet in a TCP stream or a packet. |
analog | Can take on any value to represent sound; see digital. |
ANI |
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