Half-Duplex

(adj.)Refers to the transmission of data in just one direction at a time. For example, a walkie-talkie is a half-duplex device because only one party can talk at a time. In contrast, a telephone is a full-duplex device because both parties can talk simultaneously. Duplex modes often are used in reference to network data transmissions.

Some modems contain a switch that lets you select between half-duplex and full-duplex modes. The correct choice depends on which program you are using to transmit data through the modem. In half-duplex mode, each character transmitted is immediately displayed on your screen. (For this reason, it is sometimes called local echo — characters are echoed by the local device). In full-duplex mode, transmitted data is not displayed on your monitor until it has been received and returned (remotely echoed) by the other device. If you are running a communications program and every character appears twice, it probably means that your modem is in half-duplex mode when it should be in full-duplex mode, and every character is being both locally and remotely echoed.

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

Related Articles

DocuSign

What is DocuSign? DocuSign is an agreement management application that enables businesses to create, send, and automate a wide variety of forms and contracts and...

Compliance

What is compliance? Compliance or regulatory compliance is a term used across industries to describe rules and policies that prohibit or regulate specific products, services,...

User Experience

User experience describes a user's interaction with products, systems, and services and includes usability, design, navigation, and impression.

Management Information Systems (MIS)

What is a Management Information System? A Management Information System (MIS) is an information system that provides managers with the tools to effectively organize, evaluate,...

Venture Capital

Venture capital (VC) offers startups and developing businesses growth opportunities with funding from...

Third-Party Apps

A third-party application is an application provided by a vendor other than the...

Ernst & Young (EY)

Ernst & Young Global Limited, commonly known as EY, is a multinational professional...