One of the greatest challenges associated with Internet video is bandwidth use. Video streams are bandwidth intensive. You can use codecs to do extreme compression, but even if you do so, numerous people watching a video at the same time can use excessive bandwidth. One option is to use multicast rather than unicast technology. Unicast means that the video stream goes independently to each user, and all users get their own stream. The benefit of unicast technology is that if one stream fails, it affects only one person. Multicast means that many users share the same stream, thus reducing the bandwidth requirements and network traffic. In most cases, multicasting works only in an intranet environment, because all users need simultaneous access and clear, uninterrupted data flow. Use multicasting for event broadcasting and use unicasting for on-demand video. For example, if you broadcast your company president's weekly message and all your viewers watch it at the same time, set your server to multicast the event. This setting will reduce traffic on your company's network. But if you have a video on your intranet that discusses your company's new benefits package and you want to let employees view it at their convenience, set your server to unicast the video.