At VBrick, we encounter many customer requests and issues that are specific to the enterprise, and largely irrelevant to consumer video services. One of the most prevalent is the request for ongoing support of multicast video delivery. As I read the many articles about the changing landscape of video delivery, each often neglects the needs of organizations to manage internal video streaming on their corporate network, completely behind the firewall.

Many enterprises have invested thousands, if not millions, in their networks over the last decade and those networks typically include multicast capabilities. Multicast is largely specific to internal networks, as the public internet only supports unicast video delivery. Why does this matter? There are several reasons internet streaming services lead to unsuccessful live streaming and live event initiatives, but perhaps the most important is the negative impact on network bandwidth. There is only so much space on that single internet pipe delivering connectivity to your offices and unicast video delivery simply occupies too much of that limited capacity.

So how does multicast video delivery help with this challenge? Let’s review the high-level differences between multicast and unicast.


Each user that tunes into a unicast video stream has direct contact with the streaming server. This means every user has their own, dedicated connection to the video source. When video originates from an internet-based source, each viewer has a separate video stream flowing into your office. This is why many companies do not allow employees to stream live sporting events, like March Madness basketball games, at work. Too many people watching basketball means no internet for anyone else. The same applies to using an internet-based streaming service for your executive town hall event. We see this time and time again where webcasts fail because people underestimate the effects of a large, unicast-only live streaming event. It does not scale and only leads to frustration.


This type of video delivery is similar to drawing water from a river. When people consume water from a river, they simply tap into the water from their current location on the river. Video viewers of multicast video just tap into an existing video stream that already exists. Unicast, in contrast, would be akin to having every person create their own river just to get a drink of water. Multicast video viewers do not connect to the video origin server for the feed, they view the video feed that is already streaming on the network. This basically puts no load on the server, since it’s only one video stream, as opposed to unicast where each user represents one video stream, which requires exponentially larger bandwidth capacity. Many corporate networks are ready for multicast with wired computer connections. However, we are seeing an increasing number of wireless routers ready for multicast delivery to laptops because IT administrators understand the benefits of multicast delivery on their networks, but do not want their employees tethered to their desks. The only caveat, especially in the case of video, is that a streaming device is required to convert a stream from unicast to multicast.

To recap, a 1,000-person event with internet-based, unicast video equals 1,000 connections into your office. Multicast for that same event equals just one connection into your office. You’ll just need a device that can convert the unicast feed into a multicast feed.

So that highlights the primary differences in these two variants of video delivery. In my next blog, we’ll look at the changing video player landscape and how VBrick is positioning itself for the future.

About Brian and VBrick

Brian is the Director of Product Management at VBrick – the pioneer in next-generation enterprise video through its Rev® cloud-native platform. By converting video into bandwidth-efficient streams, Rev allows organizations to use their own networks to securely share video with thousands of online viewers, centrally integrate unified communications and other video sources, and deliver a consumer-grade experience for employees.