CCITT – ComitŽ Consultatif International TŽlŽphonique et TŽlŽgraphique

Abbreviation of Comit Consultatif International T l phonique et T l graphique, an organization that sets international communications standards. CCITT, now known as ITU(the parent organization) has defined many important standards for data communications, including the following:

  • Group 3: The universal protocol for sending fax documents across telephone lines. The Group 3 protocol specifies CCITT T.4 data compression and a maximum transmission rate of 9,600 baud. There are two levels of resolution: 203 by 98 and 203 by 196.
  • Group 4 : A protocol for sending fax documents over ISDN networks. The Group 400 protocol supports images of up to 400 dpiresolution.
  • V.21: The standard for full-duplex communication at 300 baud in Japan and Europe. In the United States, Bell 103is used in place of V.21.
  • V.22 : The standard for half-duplex communication at 1,200 bps in Japan and Europe. In the United States, the protocol defined by Bell 212Ais more common.
  • V.22bis : The worldwide standard for full-duplex modems sending and receiving dataacross telephone lines at 1,200 or 2,400 bps.
  • V.29: The standard for half-duplex modems sending and receiving data across telephone lines at 1,200, 2,400, 4,800, or 9,600 bps. This is the protocol used by fax modems.
  • V.32 :The standard for full-duplex modems sending and receiving data across phone lines at 4,800 or 9,600 bps. V.32 modems automatically adjust their transmission speeds based on the quality of the lines.
  • V.32bis:The V.32 protocol extended to speeds of 7,200, 12,000, and 14,400 bps.
  • V.34 :The standard for full-duplex modems sending and receiving data across phone lines at up to 28,800 bps. V.34 modems automatically adjust their transmission speeds based on the quality of the lines.
  • V.42 : An error-detection standard for high-speed modems. V.42 can be used with digital telephone networks. See MNPfor a competing standard.
  • V.42bis:A data compression protocol that can enable modems to achieve a data transfer rate of 34,000 bps.
  • V.90: The standard for full-duplex modems sending and receiving data across phone lines at up to 56,600 bps.
  • X.25: The most popular packet-switchingprotocol for WANs.
  • X.400: The universal protocol for e-mail. X.400 defines the envelope for e-mail messages so all messages conform to a standard format.
  • X.500: An extension to X.400 that defines addressing formats so all e-mail systems can be linked together.
  • Top Articles

    Huge List Of Texting and Online Chat Abbreviations

    From A3 to ZZZ we list 1,559 text message and online chat abbreviations to help you translate and understand today's texting lingo. Includes Top...

    How To Create A Desktop Shortcut To A Website

    This Webopedia guide will show you how to create a desktop shortcut to a website using Firefox, Chrome or Internet Explorer (IE). Creating a desktop...

    The History Of Windows Operating Systems

    Microsoft Windows is a family of operating systems. We look at the history of Microsoft's Windows operating systems (Windows OS) from 1985 to present...

    Hotmail [Outlook] Email Accounts

      By Vangie Beal Hotmail is one of the first public webmail services that can be accessed from any web browser. Prior to Hotmail and its...

    Abacus Definition & Meaning

    An abacus, also known as a counting frame, is a mechanical device used...

    Legacy Code Definition &...

    Legacy code refers to source code that has been inherited from a previous...

    Unregulated Power Supply Definition...

    An unregulated power supply is a system that transforms input voltage into direct...