Glossary

auto dial

A process where your modem dials a call for you. The dialling process is initiated by sending an ATDT (dial tone) or ATDP (dial pulse) command followed by the telephone number to dial. Auto Dial is used to dial voice numbers. See command Dn.

baud rate

A term used to measure the speed of an analogue transmission from one point to another. Although not technically accurate, baud rate is commonly used to mean bit rate.

binary digit (bit)

A 0 or 1, which reflects the use of the binary numbering system. It is used because the computer recognises either of two states, OFF or ON.

The shortened form of binary digit is bit.

bit rate

This refers to the number of binary digits, or bits, transmitted per second (bps). It is also referred to as transmission rate. Communications channels using telephone channel modems are established at set bit rates, commonly 2400, 4800, 9600, 14,400, 28,800 and higher, e.g. when using the Public Switched Telephone Network (PSTN).

bits per second (BPS)

This is the bits (binary digits) per second rate. Thousands of bits per second are expressed as kilobits per second or kbps.

buffer

A memory area set aside to be used as temporary storage during input and output operations. An example is the modem's command buffer.

byte

A group of binary digits stored and operated upon as a unit. In user documentation, the term usually refers to 8-bit units or characters. One kilobyte (KB) is equal to 1,024 bytes or characters; 640 KB indicates 655,360 bytes or characters.

carrier

A tone signifying a connection the modem can alter to communicate data across telephone lines.

56K Voice Faxmodem Internal - User’s Guide

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3Com 1.024.1644-00 Glossary Auto dial, Baud rate, Binary digit bit, Bit rate, Bits per second BPS, Buffer, Byte, Carrier