Multicast decreases bandwidth consumption and, with minimal programming and coordination, allows developers to deploy applications in new ways using channels that have current data. Multicast is particularly valuable for satellite providers that use fast, scarce bandwidth to provide news, stock, video, game, and general replication update feeds over single channels to entire cities. Technologies like JRMS offer the basis to achieve multicast-aware applications. In this article, I will introduce some examples of JRMS that you can use in your own network. For example, you could multicast n radio stations on n ports for a large population of Internet users.
Net applications are mostly unicast.
So 1 million users employing a unicast approach require 1 million different ports, and each packet must be duplicated 1 million times. Many vendors of applications and services in the video, audio, and generic data feed market do not use multicast. Multicast is not yet widely available, so the Internet cannot efficiently deliver the same information to many users. As networking technology improves and bandwidth increases, multicast-aware applications may become more common. JRMS examples from Sun JRMS team Download the JRMS API from Sun and try a few of the examples.