DESCRIPTION OF COMMUNICATION STANDARDS. INCLUDES MODEM & FAX. --------------------------------------------------------------------------- STANDARD NAME DESCRIPTION --------------------------------------------------------------------------- CCITT v.21 Standard for 300 bps. (FSK). Bell 103J Bell 202 Old standard for 1200 bps, half duplex. Leased lines. CCITT v.22 Standard for 1200 bps. (DPSK). Bell 212A CCITT v.22bis Standard for 2400 bps. (DPSK). CCITT v.26ter Standard for 2400 bps with echo cancellation. Bell 208 Standard for 4800 bps. Used on leased lines. CCITT v.27ter Standard for G3 FAX at 4800 bps with fall back to 2400 bps. CCITT v.29 Standard for G3 FAX at 9600 bps with fall back to 7200 and 4800 bps. Also v.27ter/v.29 is used by CompuCom modems. Half duplex. Reverse direction bps (slow?). CCITT v.32 Standard for 9600 bps with echo cancellation. Fall back to 4800 bps. Both direction simultaneously. (QAM). CCITT v.32bis Standard for 14400 bps with echo cancellation. Fall back to 12000, 9600, and 7200 bps. (TCM). Both directions simultaneously. CCITT v.33 14400 with fall back to 12000 bps. Used for what? USR HST14400 US Robotics HST modulation. 14400 bps in one direction and 450 bps in reverse direction. Fall back to 12000, 9600, and 4800 bps. Trailblazer Proprietary and fast! Up to 18000 bps. ??? Hays V-Series Proprietary full-duplex 9600 baud. Hays its own CCITT LAP-B error correction and its own scheme for data compression. EIA Class2 FAX Fax standard called G2. ??? CCITT v.FAST Standard for 19200 bps or slightly higher. Uses echo CCITT v.32bisbis canellation and is not FINALIZED. The first modems will be available in late 1993. The name of the standard has not been determined yet. It will have a much greater capability to adapt modem speeds to meet existing conditions (more than any existing modem). Theory sets a limit in the low 20000 bps range. This will probably be the LAST analog modem standard. NOTE: This prediction was incorrect. The V.FAST standards (V.FC/V.34) are 28,800 BPS. V.FC was available in Early '94, V.34 in Late '94. Addendum: V.FC 19200, 21600, 24000, 28800 BPS. Predecessor to V.FAST (V.34). Engineered by Rockwell, Inc. Methods to be used in ITU V.34 Standard. V.34 (V.FAST) 19200, 21600, 24000, 28800 BPS. Ratified V.FAST standard, based on V.FastClass (V.FC.) ISDN Integrated Services Digital Network. This uses fiber optic cable. It is currently available in larger cities within 3 miles (has been lengthen) of the central office. Available in two flavors: Primary Rate Interface service and Basic Rate Interface service. Basic, also known as 2B+D provides users with two 64Kbit/sec channels for voice and data and one 16Kbit/sec channel used by the carrier for call setup and network management. The primary, also known as 23B+D provides 23 64Kbit/sec channels and one 16Kbit/sec channel. Some recent west coast subscribers will be paying a one time $75 fee for a network connection device and $97 per month for service, which includes two voice lines. SMDS Switched Multi-Megabit Data Service. Uses fiber optics. ??? HDSL High-rate Digital Subscriber Link. Bell Labs and Bellcore have recently developed this technology. It is capable of carrying 1.5 megabits/sec over copper phone lines! Limited to about 3 miles from the central office. Benificial since it provides high speed data rate without running new fiber optic cable to the customer. This is still in the labs. --------------------------------------------------------------------------- MODE BPS BAUD MODULATION NOTES --------------------------------------------------------------------------- v.33 14400 2400 128-TCM v.33 12000 2400 64-TCM V.34 28800 2400 512-TCM V.FC 28800 2400 512-TCM v.32bisbis 19200 2400 512-TCM Was proposed V.34. Nonexistant. v.32bis 14400 2400 128-TCM v.32bis 12000 2400 64-TCM v.32bis 9600 2400 32-TCM v.32bis 7200 2400 16-TCM v.32 9600 2400 32-TCM v.32 9600 2400 16-QAM Uncoded v.32 4800 2400 4-DPSK v.29 9600 2400 16-QAM v.29 7200 2400 8-QAM v.29 4800 2400 4-DPSK v.27ter 4800 1600 8-PSK v.27ter 2400 1200 4-DPSK G3 FAX -> -> -> According to v.29/v.27ter v.22bis 2400 600 16-QAM v.22 1200 600 4-DPSK Same as BELL 212A ISDN 65536 65536 FiberOptic Digital The baud rate over the phone line means that more than two tones are used at the baud frequency to achieve the bps rate. 4-DPSK means four tones... --------------------------------------------------------------------------- NAME DESCRIPTION OF ERROR CORRECTION AND DATA COMPRESSION --------------------------------------------------------------------------- MNP1 Hardware error correction. MNP2 Hardware error correction. MNP3 Hardware error correction. Strips off start and stop bits during transmission over phone line. MNP4 Hardware error correction. Fastest way to send compressed files. Strips off start and stop bits during transmission. Also adapts to line conditions. MNP5 Hardware error correction and data compression (up to 2 time compression on TEXT). Do NOT use on compressed files! MNP6 Additional Universal Link Negotiation and Statistical Duplexing to MNP5 service MNP7 Additional Enhanced Data Compression with MNP4. MNP8 Nothing available ??? MNP9 Additional Enhanced Data Compression with v.32 modems Also adds Enhanced Universal Link Negotiation, which allows connection to both MNP and non-MNP modems at the highest performance level. MNP10 Hardware error correction and data compression. Special! v.42 CCITT error correction. LAPM. Fastest way to send compressed files. Strips off start and stop bits during transmission. v.42bis CCITT data compression (up to 4 time compression on TEXT). Uses a version of the Lempel-Ziv data compression algorithm. --------------------------------------------------------------------------- baud means Actual rate of symbols trasmitted per second. bps means Bits Per Second. MNP means Microcom Networking Protocol. CCITT means International Telephone and Telegraph Consultative Committee. FSK means Frequency Shift Keying. DPSK means Phase Shift Keying. QAM means Quadrature Amplitude Modulation. Combination of PSK and AM. TCM means Trellis Coded Modulation. LAPM means Link Access Procedure for Modems. --------------------------------------------------------------------------