This is a review of [the previous article](https://www.brightcove.com/ja/resources/blog/ecdn-introduction-1/ “the previous article”), but when using a cloud-based video distribution service like [Brightcove](https://www.brightcove.com/ja/products/player/ “Brightcove”) to distribute videos internally, the number of viewers of the video is the number of video streams.
For example, if 100 people are watching a video stream with a bitrate of 500kbps (500k data transfers per second), 50mbps of data transfer is required. This is a problem for network administrators, as it can affect other systems, but ramp’s eCDN solution, Altitude CDN™, is a solution to this problem.
Altitude CDN™ is made up of three solutions: Multicast+, OmniCache™, and Altimeter.
Multicast+ is an eCDN solution that solves the problems faced by those who want to use live streaming within their company, and as the name suggests, it requires a multicast environment.
Multicast is suitable for video distribution because it can communicate with multiple terminals with a single packet, and has a lower network failure rate than unicast, but unfortunately there are few examples of multicast routing being implemented in Japan. However, if your company’s network environment is multicast, it is extremely easy to introduce Multicast+.
## Multicast+ Overview Diagram
Install Multicast+ on each PC terminal in your company (compatible with various OSs), and use the Altimeter management software to set up the terminal that will receive the Brightcove videos in the cloud (Primary Sender). This will prepare the video viewer (Receiver) to receive the videos from the Primary Sender rather than Brightcove.
After that, by setting the internal IP addresses that will be used for distribution in Altimeter, the video viewers (Receivers) will be able to receive videos from the Primary Sender without accessing external networks. As a result, this is a system that makes it possible to perform live distribution without putting a strain on the network.
