3Com 005605-00 Manual

Contents

GLOSSARY91characters per second (CPS)A data transfer rate generally estimated fromthe bit rate and the character length. Forexample, at 2400 bps, 8-bit characters withstart/stop bits (for a total of ten bits percharacter) will be transmitted at a rate ofapproximately 240 characters per second(cps). Some protocols, such as error-controlprotocols, employ advanced techniques suchas longer transmission frames and datacompression to increase cps.class 1 and 2.0International standards used by faxapplication programs and faxmodems forsending and receiving faxes.cyclic redundancy checking (CRC)An error-detection technique consisting of atest performed on each block or frame of databy both sending and receiving modems. Thesending modem inserts the results of its tests ineach data block in the form of a CRC code.The receiving modem compares its results withthe received CRC code and responds witheither a positive or negative acknowledgment.data communicationsThe transmission or sharing of data betweencomputers via an electronic medium.