braun@dri.com (Karl T. Braun (kral)) (05/09/91)
I now have a more comprehensive V.* standards reference list, thanx to uunet!hayes!tnixon and uunet!faui09.informatik.uni-erlangen.de!mskuhn Below is the list as I have it, which is a great quick reference format; just "grep '^V.whatever'" on the file, and you get a short description of the standard, possibly in two forms. Enjoy. >From uunet!hayes!tnixon Mon May 6 18:33:32 1991 + +CCITT-standards + V.1 Defines binary 0/1 bits as space/mark line conditions V.2 Limits power levels of modems used on phone lines V.4 Sequence of bits within a character as transmitted V.5 Standard synchronous signalling rates - dialup lines V.6 Standard synchronous signalling rates - leased lines V.7 Vocabulary V.10 Unbalanced high-speed electrical interface characteristics V.11 Balanced high-speed electrical characteristics V.13 Simulated carrier control (full duplex modem used as half duplex) V.14 Asynchronous to synchronous conversion V.15 Acoustic couplers V.16 Electrocardiogram transmission on phone lines V.17 Application-specific modulation scheme for Group 3 fax(7.2,9.6,120,144) (provides 2-wire half-duplex trellis-coded transmission at 7200, 9600, 12000, and 14400bps.) V.19 DTMF modems (low-speed parallel transmission) V.20 Parallel data transmission modems V.21 300 bps V.22 1200/600 bps FDX V.22bis 2400 bps V.23 1200/75 bps (host tx 1200, rx 75, terminal tx 75, rx 1200) [Actually, V.23 can have only one channel or the other or both, and the channels are INDEPENDENT (not necessarily in reverse directions). The setup you've noted is typical of Prestel and other applications, but only one of many supported. V.23 also supports 600bps in the high speed channel.] +V.24 known as EIA RS-232 in the USA [V.24 defines ONLY the functions of the circuits. EIA-232-E (which is how the current version of the standard is designated) also defines electrical characteristics and connectors. The 232-equivalent electrical characteristics are defined in CCITT V.28, and the equivalent connectors are defined in ISO 2110.) V.25 Automatic answering equipment and parallel automatic dialing (defines the 2100Hz "answer tone" that modems send) V.25bis Serial automatic calling and answering -- CCITT equiv of AT cmds) [this is the current CCITT standard for modem control by computers via serial interface(in the USA, we use primarily the Hayes AT command set)] V.26 2400 bps 4W V.26bis 2400/1200 bps HDX V.26ter 2400/1200 bps FDX V.27 4800 bps 4W V.27bis 4800/2400 bps 4W V.27ter 4800/2400 bps FDX [V.27ter is also used in a half-duplex 2-wire mode to implement the 2400 and 4800bps transmission schemes in Group 3 fax] V.29 9600 bps 4W [V.29 is also used in a half-duplex 2-wire mode to implement the 7200 and 9600bpss transmission schemes in Group 3 fax] V.31 (Rarely used) older electr'l characteristics based on contact closure (like old teletypes) V.31bis The above, using optocouplers V.32 9600/4800 bps FDX V.32bis Ext'n of V.32; adds 7.2, 120, and 144kbps ops & rapid rate renegotiation V.33 14.4 kbps [and 12000bps, for 4-wire leased lines] V.35 48 kbps 4W [The CCITT no longer recommends the use of V.35, since it was made obsolete by V.36. However, many computers and other equipment still use the electrical interface specified in Appendix 2 of V.35, and an particular ISO connector -- and call it a "V.35" interface (although this is a misnomer)] V.36 48 kbps 4W V.37 72 kbps 4W [V.36 and V.37 are not really "4-wire" modems. They are GROUP BAND modems, which means they combine several telephone channels (not just one).] V.40 How teletypes indicate parity errors V.41 An older, obsolete error control scheme V.42 Error-correcting procedures for modems using async-to-sync conversion (V.22, V.22bis, V.26ter, V.32, V.32bis); defines LAPM protocol, and provides fallback to MNP4 V.42bis Lempel-Ziv-based compression scheme for use with V.42 LAPM V.50 Standard limits for transmission quality for modems V.51 Maintenance of international data circuits V.52 Apparatus for measuring distortion and error rate for data transmission V.53 Impairment limits for data circuits V.54 Loop test devices for modems V.55 Impulse noise measuring equipment V.56 Comparative testing of modems V.57 Comprehensive test set for high speed data transmission V.100 Interconnection between PDNs and PSTNs (Public Data Networks, Public Switched Telephone Networks) V.110 ISDN terminal adaption V.120 ISDN terminal adaption with statistical multiplexing V.230 General data communications interface, layer 1 >From uunet!faui09.informatik.uni-erlangen.de!mskuhn Tue May 7 13:54:57 1991 The CCITT Blue Book, Volume VIII, Fascicle VIII.1 contains the CCITT series V recommendations on "data communication over the telephone network. Some of the recomendations you didn't have in your list are: V.1 "Equivalence between binary notation Symbols and the significant conditions of a two-condition code" (what is 0 and what is 1 on the line). V.2 "Power levels for data transmission over telephone lines" V.4 The usual asynch format of ASCII characters, parity, start/stop bit etc. V.5 a list of possible transmission speeds V.6 a list of possible transmission speeds V.7 a list of terms concerning modems in English, Spanish, French V.10 = RS-423, modem interface for 100kbit/s V.11 = RS-422, modem interface for up to 10Mbit/s V.13 "Simulated carrier control" V.14 asynch data on synch lines V.15 acoustic coupling V.16 medical analogue modems V.28 electrical characteristics for V.24 V.35 data transmission at 48 kbp/s using 60-108 kHz group band circuits V.42 error correcting procedures for DCEs using asynch-to-synch conversion V.50 limits for transmission quality V.54 "Loop test devices for modems" V.56 "Comparative tests of modems for use over telephone-type circuits" V.57 "Comprehensive data test for high data signalling rates" V.100 V series interfaces and ISDN V.230 "General data communications interface layer 1 specification" The list is not complete, but contains most of the stuff. You can order this Fascile of the Blue Book for some $s at Union Internationale des telecomunications Place des Nations 1211 Geneve 20 Switzerland -- kral * 408/647-6112 * ...!uunet!drivax!braun * braun@dri.com Whoever is calm and sensible is insane -- Rumi