Multicast routing:
Multicast routing is a networking method for efficient distribution of one-to-many traffic. A multicast source, such as a live video conference, sends traffic in one stream to a multicast group. The multicast group contains receivers such as computers, devices, and IP phones.
Internet Protocol (IP) multicast is a bandwidth-conserving technology that reduces traffic by simultaneously delivering a single stream of information to thousands of recipients and homes. IP multicast delivers source traffic to multiple receivers without adding any additional burden on the source or the receivers.
Applications like videoconferencing, corporate communications, distance learning, and distribution of software, stock quotes, and news use IP multicasting.
If IP multicast is not used, a source is required to send more than one copy of a packet or an individual copy to each receiver. In such case, high-bandwidth applications like Video or Stock where data is sent more frequently and simultaneously, use a large portion of the available bandwidth. In these applications, the only efficient way of sending information to more than one receiver simultaneously is by using IP multicast.
Common uses include these technologies: