3Com OfficeConnect 56K Business, Command Reference Manual

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G
LOSSARY
3
copies of transmitted frames until they are positively acknowledged by
the receiving modem.
byte A group of binary digits stored and operated upon as a unit. A byte
may have a coded value equal to a character in the ASCII code (letters,
numbers), or have some other value meaningful to the computer. In
user documentation, the term usually refers to 8-bit units or characters.
1 kilobyte (K) is equal to 1,024 bytes or characters; 64K indicates
65,536 bytes or characters.
call indicate A call originating tone defined by ITU-T recommendation V.8.
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.
central office (CO) The facility to which devices, such as telephones, fax machines, and
modems within a specific geographic area of a public telephone
network are connected.
central office switch A device, located at the telephone company's central office, to which
devices, such as telephones, fax machines, and modems are connected.
character A representation, coded in binary digits, of a letter, number, or other
symbol.
characters per second
(cps)
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
HST and MNP, employ advanced techniques such as longer transmission
frames and data compression to increase cps.