What Does Multicast Mean?

Multicast is a communication method and data delivery scheme in which a single source sends the same data to multiple receivers simultaneously. It is similar to broadcasting but more secure because it has an added bonus of receiver discretion, where the data is received by specific users or hosts.


Techopedia Explains Multicast

The multicast process involves a single sender and multiple receivers. versus systems that are designed to be connection-dependent, like a client-server system. User datagram protocol (UDP) is the most common protocol used with multicasting.

Email is the best example of multicast, where a user can choose to send mail to many different addresses, rather than a complete contact list. Another example is the one-to-many multicasting of a streaming video toward many users from a single server. Another good example is Internet protocol (IP) multicasting, where network nodes, like switches and routers, handle data packet replication through multicast groups.

Non-IP based multicast implementations include Internet Relay Chat (IRC), which is well scaled for large numbers of small groups.


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Margaret Rouse
Technology Expert

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.