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Brian Cryer's Glossary of IT Terms with Links

Analogue Modem

analogue modem
A modem for use with analogue equipment, such as a phone line. Typical analogue modem speeds are:
Common name Maximum download speed Maximum upload speed
kbps bytes/sec kbps bytes/sec
4.8 4.8 600 4.8 600
9.6 9.6 1200 9.6 1200
14.4 14.4 1800 14.4 1800
28.8 28.8 3600 28.8 3600
33.6k 33.6 4200 33.6 4200
56k v90 53 6600 33.6 4200

Modems can operate at speeds much slower than their rated maximum.

Where a cable modem has LEDs on the front, these are typically one or more of:

LED Short for Description
PWR Power Power-on/ready indicator.
MR Modem Ready
AA Auto Answer Modem is ready to answer incoming calls.
CD Carrier Detect Indicates that the modem has detected a valid carrier signal from the remote modem. (When modems communicate they establish a carrier signal for handshaking purposes.)
HS High Speed Indicates if the connection is considered by the modem to be "High Speed" this is at the modem's top speed or above 4800bps (depending on the modem).
RD Receive Data Flashes when the modem is receiving data (from the modem at the other end of the link.)
SD Send Data Flashes when the modem is sending data (to the modem at the other end of the link).
TR Terminal Ready On indicates that the computer (that the modem is locally connected to) is ready to receive data.
CS Clear to Send On indicates that the modem is ready to receive data from the computer it is connected to.
ARQ/FAX Error correction fax  
OH Off Hook Indicates that the phone line is active and the modem has control of the line.

See also: cable modem.

For more information see:

  • www.v90.com - Information about the V90 modem standard.