The data was taken two bits at a time and thus could be as: 00, 01, 10, and   
   11. Accordingly, the 4 possible phase changes could be directly related to   
   these (4) bit sequences. Now, in this example, the changing of the phases   
   was in line with every other bit, and so at half the bit rate. It was   
   therefore said to have a Baud Rate of half the Bit Rate.   
      
   So for 1200 bits per second data, the Baud Rate was 600. This extrapolation   
   was actually used in ITU-T Recommendation V.26. Given this fact, it is hard   
   to fault anyone for following it.   
      
   That is basically the end of the extrapolation, or at least it should have   
   been!  It was finally recognized as being inappropriate and is no longer   
   used. If you did a search of Recommendation V.32bis or V.34 you would find   
   that the word Baud is not used in any context. It is simply not found in   
   the recommendations at all. Why then are so many people saying things like   
   the baud rate of V.32bis is 2400? Simply, it is because magazine articles   
   and so-called experts continue to use this poor and improper extrapolation.   
   It is also why so many people try to explain it in different ways and   
   always seem to be in conflict with each other. Frankly, there is NO correct   
   explanation or description.   
      
   BIT - Acronym for (Bi)nary Digi(t) (ie. 0 or 1). As used in the context of   
   this forum the bit is a basic unit of data.   
      
   BPS - (B)its (P)er (S)econd - the unit of measure which refers to the data   
   transfer rate between communications devices. The unit by which raw modem   
   throughput is rated.   
      
   BYTE - Typically a group of 8 binary digits, but can vary from 6 to nine   
   bits depending on the platform. It is a basic unit of memory used to store   
   data in a computer.  Additionally, it is the basic element size used when   
   expressing ASCII characters such as you see typed here. [See OCTET]   
      
   CAS - IBM and DCA standard for computer-fax modem interface.   
      
   CCITT - Comite Consultatif International Telegraphique et Telephonique   
   (French for The International Telegraph and Telephone Consultative   
   Committee). Now known as ITU-T (International Telecommunications Union-   
   Telecommunication Standards Sector).   
      
   CLASS - "Classes" refer to the standards defined by technical subcommittee   
   TR-29.2 of the Telecommunications Industry Association (TIA) in the USA.  A   
   "Class" (or, formally, Service Class) is a set of capabilities of a fax   
   MODEM (not a fax machine) which is controlled by an extension of the Hayes   
   AT Command Set.  Class 1 defines only a few commands (about 10), and   
   provides the minimal set of hardware features in the modem necessary to   
   support fax transmission and reception. Class 2 defines a much larger set   
   of commands (mostly parameters), and requires the modem to implement the   
   ITU-T T.30 fax protocols in the modem firmware.   
      
   Because the "Class" of a device refers only to the way that fax software   
   talks to the modem and not to how the device works across the phone line   
   with other fax devices, the Class has no bearing on interoperability   
   (assuming, of course, the modem firmware and fax software are correctly   
   implemented!).  Class 1 and Class 2 modems and other Group 3 fax devices   
   can communicate with each other across the phone line, in any combination.   
      
      Class1 - Electronic Industries Association/Telecommunications Industry   
      Association standard for minimal computer-fax modem interface. EIA-578   
      
      Class2.0 - EIA/TIA standard for extended computer-fax modem interface.   
      EIA-592 specifies Class 2.0 "Class 2" is a non-standard based on an   
      obsolete draft.   
      
   CO - Central Office, the telephone company's central switching station   
   for a given area.   
      
   CPS - (C)haracters (P)er (S)econd - unit of measure for the conjugate data   
   transfer rate, in bytes, between modems. From a user's perspective, this is   
   the bottom line measure of a modem's throughput performance.   
      
   CRC - (C)yclic (R)edundancy (C)hecking {or Checksum} - an error-detection   
   technique consisting of a cyclic algorithm performed on each block or frame   
   of data by both sending and receiving modems or transfer protocols.   
      
   CTS - (C)lear (T)o (S)end - flow control parameter which indicates that a   
   device is ready to receive data.   
      
   DCE - (D)ata (C)ommunication {or Circuit-Terminating} (E)quipment - applies   
   to the device that establishes and controls the data link via the telephone   
   network (eg. a modem). When referring to data flow rates, it is the rate of   
   raw data flow between two modems.   
      
   DS-0 - The base unit of digital transmission capacity. 1 communication   
   channel = 1 simultaneous voice grade equivalent with a communication   
   capacity of 64 thousand bits per second (64Kbps)   
      
   DS-1 (T1) - The equivalent of 24 multiplexed voice grade channels (DS-0s).   
   1.544 million bits per second (1.5Mbps)   
      
   DS-1C - The equivanlent of 2 multiplexed T1 channels. 3.15Mbps   
      
   DS-2 (T2) - The equivalent of 4 multiplexed T1 channels. 6.312 million bits   
   per second (6.3Mbps)   
      
   DS-3 (T3) - The equivalent of 28 multiplexed T1 channels. 44.736 million   
   bits per second (45Mbps)   
      
   DS-4 (T4) - The equivalent of 6 multiplexed T3 channels. 274.176 million   
   bits per second (274Mbps)   
      
   DSP - (D)igital (S)ignal (P)rocessor - a semiconductor optimized for   
   handling auio or video signals.   
      
   DSVD - (D)igital (S)imultaneous (V)oice and (D)ata   
      
   DSZ -  a shareware X,Y, and Zmodem protocol driver marketed by Omen   
   Technology that is most noted for its proprietary extensions/improvements   
   to the base Zmodem protocol.   
      
   DTE - (D)ata (T)erminal {or Terminating} (E)quipment - The device that   
   generates or is the final destination of data (eg. a computer). When   
   referring to data flow rates, it references to the rate of raw data flow   
   between a computer and modem.   
      
      
   --- MPost/2 v2.0a   
    * Origin: Marsh BBS (c) Dawson Creek BC Canada (1:17/23)