| ADPCM |
Adaptive Differential Pulse Code modulation. A technique used to transmit
data with a rate of 32Kbps |
| ANSI |
American National Standards Institute |
| ASCII |
American Standard Code for Information Interchange |
| ATM |
Asynchronous Transfer mode. A technique used to transmit data in cells of
53 bytes |
| Auto answer |
A feature of modems to answer automatically in phone calls for data
communication |
| Baud rate |
Modulating speed for analogue signals |
| BCD |
Binary coded decimal. Binary code for decimal digits 0 to 9. |
| BPS |
Bit per second. BPS is a transfer rate unit |
| Busy
Tone |
A tone advising the caller
that the telephone number is busy. |
| Call
Waiting Tone |
A tone advising the user
of the call waiting supplementary service who is engaged on a call that someone is attempting to call his number |
| Carrier |
Signal of a specific frequency that is modulated and carries
information |
| CCIT |
International Telegraph and Telephone Consultative Committee. |
| Codec |
Coder decoder |
| Compression |
Data compression technique for faster transmission |
| Congestion
Tone |
A tone advising the caller
that the groups of lines or switching equipment necessary for the setting-up of the required call or for the use of
a specific service are temporarily engaged. |
| CRC |
Cyclic Redundancy Check. Error control checking |
| CTS |
Clear to send. A
signal used in RS232 interface for data
manipulation |
| Datagram |
Message routing method used in packet switching where every packet is transferred
independently from the previous packet in the same message |
| Dial
tone |
A tone advising that the
exchange is ready to receive call information and inviting the user
to start sending call information |
| db |
Decibel. A measuring unit of the ratio of two quantities |
| DTE |
Data terminal equipment |
| FDM |
Frequency division multiplexing |
| FDX |
Full duplex. |
| ISO |
International Standard
Organization. |
| ISDN |
Integrated Services Digital Networks. |
| LDM |
Limited distance modem. |
| Off-hook |
The status of the phone when we have lifted the handset |
| On-hook |
The status of the handset when it is on the phone. |
| PABX |
Private Automatic Branch Exchange. |
| Pay
Tone |
A tone advising users of a
payphone that a payment is required. |
| PBX |
Private Branch Exchange |
| PCM |
Pulse Code Modulation |
| POTS |
Plain Old Telephone System |
| PSTN |
Public Switched Telephone Network |
| QAM |
Quadrature Amplitude modulation |
| Ringing
tone |
A tone advising the caller
that a connection has been made and that a calling signal is being applied to a telephone number or service point. |
| RTS |
Request to send |
| SNR
|
Signal to noise ratio |
| Special
Information Tone |
A tone advising the caller
that the called number cannot be reached for reasons other
than "subscriber busy" or "congestion".
The tone may also be used in conjunction with recorded announcements
to signify that what the caller is about to
hear is a recording. It should always be used to precede all call
failure announcements. |
| TDM |
Time division multiplexing |
| URL |
Universal Resource locator
|
