Communications Protocol

All communications between devices require that the devices agree on the format of the data. The set of rules defining a format is called a protocol. At the very least, a communications protocol must define the following:

  • rate of transmission (in baud or bps)
  • whether data is to be transmitted in half-duplex or full-duplex mode
  • In addition, protocols can include sophisticated techniques for detecting and recovering from transmission errors and for encoding and decoding data.

    The table lists the most commonly used protocols for communications via modems. These protocols are almost always implemented in the hardware; that is, they are built into modems.

    In addition to the standard protocols listed in the table, there are a number of protocols that complement these standards by adding additional functions such as file transfer capability, error detection and recovery, and data compression. The best-known are Xmodem, Kermit, MNP, and CCITT V.42 . These protocols can be implemented either in hardware or software.

    Vangie Beal
    Vangie Beal
    Vangie Beal is a freelance business and technology writer covering Internet technologies and online business since the late '90s.

    Top Articles

    The Complete List of 1500+ Common Text Abbreviations & Acronyms

    Text Abbreviations reviewed by Web Webster   From A3 to ZZZ we list 1,559 SMS, online chat, and text abbreviations to help you translate and understand...

    How to Create a Website Shortcut on Your Desktop

    Website Shortcut on Your Desktop reviewed by Web Webster   This Webopedia guide will show you how to create a website shortcut on your desktop using...

    Windows Operating System History & Versions

    The Windows operating system (Windows OS) refers to a family of operating systems developed by Microsoft Corporation. We look at the history of Windows...

    First to Fifth Generations of Computers

    Reviewed by Web Webster   Learn about each of the 5 generations of computers and major technology developments that have led to the computing devices that...

    Hackerspace Definition & Meaning

    What is a hackerspace? A hackerspace, also known as a hacklab, incubator, or hackspace,...

    Random Access Memory (RAM)...

    Random Access Memory (RAM) reviewed by Web Webster   Random Access Memory (RAM) is a...

    OEM – original equipment...

    OEM - Original Equipment Manufacturer reviewed by Web Webster OEM (pronounced as separate letters)...