Public Broadcasting Service

In this weekly website column, I, Cringley: The Pulpit, the subject is multicasting, an internet broadcasting technology with the potential "goal of making everybody a broadcaster." The article reviews a new technology which has the ability to stream live television (TV) on the internet, claiming to be able to carry live programming with no more than a 10 second total end-to-end delay, through using the ability of individual computers to forward broadcast information to each other simultaneously.

The author describes the ability that this new technology would give to local television stations or established networks to place content directly onto the internet. He states that it has news implications, for example, of allowing a webcam (web-linked video camera) to be set up in a location where current news is of international importance (examples used are Darfur and Baghdad) in order to show news that could serve "a truly global audience."

Rather than use of bandwidth to download video from a source, this particular Internet Protocol (IP) service allows many hosts to share a multicast address and, through that address, receive the same content, or peer-to-peer video streaming access (P2P). Historically, according to the author, "Multicasting was seen as the most efficient way for one computer to talk simultaneously to a million others, and that capability has been built into every router pretty much since the beginning, though generally not enabled by the network administrator." Throughout several decades of debate and experiment with balancing bandwidth usage and router speed and capacity, the use of multicasting was apparently a technically unsound option for television broadcast.

As stated here, a P2P technology called Neokast, developed by Stefan Birrer of Northwestern University, effectively emulates multicasting. Neokast is not a video technology, it is a networking technology. It is presently (March 2007) operating as a .NET application limited for the moment to Windows computers (and, according to a comment added to the article, Linux). It is a player that can operate as a stand-alone application or a browser plug-in, allowing a viewing experience of connecting to a video stream in progress, much like cable or broadcast TV, and unlike downloading a file. "Under normal circumstances the client does not end up with a local copy of the complete video, the P2P caching aspect of the product being limited to a few seconds or at most minutes of content. This makes video rights management much easier and ought to appeal to TV networks and movie studios." It also, according to the author, a technology that is "polite" about bandwidth usage because it allows a single copy to be accessible inside a local subnet, trading inexpensive intranet bandwidth for expensive internet bandwidth.