USRobotics V.34 - Manual (Page 213)

COURIER HIGH SPEED MODEMS
J-4 Glossary
Carrier
A continuous frequency capable of being either modulated or
impressed with another information-carrying signal. Carriers
are generated and maintained by modems via the transmission
lines of the telephone companies.
CCITT
Formerly, an international organization that defined standards
for telegraphic and telephone equipment. It has been
incorporated into its parent organization, International
Telecommunication Union (ITU). Telecommunication
standards are now covered under Telecommunications
Standards Sector (TSS). ITU-T replaces CCITT. For example,
the Bell 212A standard for 1200 bps communication in North
America was referred to as CCITT V.22. It is now referred to as
ITU-T V.22.
Character
A representation, coded in binary digits, of a letter, number, or
other symbol.
Characters Per Second
A data transfer rate generally estimated from the bit rate and
the character length.
For example, at 2400 bps, 8-bit characters with Start and Stop
bits (for a total of ten bits per character) will be transmitted at a
rate of approximately 240 characters per second (cps). Some
protocols, such as USR-HST and MNP, employ advanced tech-
niques such as longer transmission frames and data com-
pression to increase cps.
Class 1/EIA-578
An American standard used between facsimile application
programs and facsimile modems for sending and receiving
Class 1 faxes.
Class 2.0/EIA-592
An American standard used between facsimile application
programs and facsimile modems for sending and receiving
Class 2.0 faxes.