line sharer

Definition of line sharer in The Network Encyclopedia.

What is Line Sharer?

A device that allows many devices to share the same line.

Examples of line sharers include the following:

  • Host line sharers:
    Allow multiple terminals or other data terminal equipment (DTE) to be connected to an asynchronous mainframe host over a single, shared serial transmission line using V.35 adapters and cable. You can use host line sharers primarily to broadcast data to the DTEs. Data transmitted by the DTEs can also be buffered in the line sharer until the line is free and the data can be sent to the host. Host line sharers typically use either RS-232 or V.35 serial interface connections.


  • PSTN line sharers:
    Allow multiple Public Switched Telephone Network (PSTN) devices, such as phones, fax machines, and modems, to share one or more phone lines by using RJ11 connectors and adapters. You can often program PSTN line sharers to switch between devices based on calling tones, so that you can remotely control data collection equipment over modems in industrial environments. A small line sharer might let you connect four phones or other devices to two shared phone lines for a small office/home office (SOHO). Other line sharers connect large numbers of phones to a relatively small number of phone lines on a first-come, first-served basis in modem-pooling environments.

    Graphic L-10. Three varieties of line sharer.

  • Internet line sharers:
    Typically stand-alone devices that together with RS-232 modem adapters allow several PCs to share one modem for dial-up connection to the Internet. Internet line sharers typically use one IP address to allow multiple users to browse the Internet simultaneously.