All things related to multicast

[Bill Owens <>]

On Mon, Dec 17, 2012 at 03:20:50PM -0500, Gurcharan S. Khanna wrote:
> hi,
> 
> regarding multicast sources and its uses, i have been building up the RIT 
> Global Collaboration
> Grid based on primary multicast sources. i have about a dozen mulitcast 
> streams, some at full
> HD and 20 Mbps going 24/7 within the 233.17.33.xxx range. these are being 
> received
> on-campus at a dozen sites and also at our foreign campuses via multicast 
> bridges at the moment.
> we use the same system for events, such as lectures, demos, classes, etc. 
> as required.

In a backwards way that use case makes the argument for dropping interdomain 
multicast; you're using true multicast on campus, where it generally works 
well and isn't too hard to maintain, and resorting to unicast in the wide 
area (which is why I don't see your sources as active multicast groups in the 
backbone network). There is some bandwidth duplication involved if more than 
one remote campus wants to see the content, but other than that the system is 
approximately as efficient in network resource use as a true multicast 
configuration. And without the complex, difficult to 
implement/maintain/troubleshoot interdomain multicast support.

Bill.