Multicast Internet Route table.

Corey Touchet corey.touchet at
Tue Sep 2 15:29:26 UTC 2014

14 years at Verizon Wireless and I despised the crop of multicast products
that seemed to pop up from time to time.  Even in a fully controlled
network multicast remains at best black magic.  There are ways to make it
more reliable and prevent people from ruining the setups especially for
PIM type setups, but I would agree with others, unicast has better
advantages though you have to keep up with the bandwidth curve.  Content
delivery systems moving the content closer to edge customers makes this
less of a problem as well.

Torrent style distribution appears to be particularly effective as long as
you can maintain a pool of users to distribute the content.  Blizzard has
made good progress using this for game updates will a fallback to http if
you canĀ¹t get the content via torrents.

On 9/2/14, 6:46 AM, "John Kristoff" <jtk at> wrote:

>On Tue, 2 Sep 2014 04:47:37 +0000
>"S, Somasundaram (Somasundaram)" <somasundaram.s at>
>> 1: Does all the ISP's provide Multicast Routing by
>> default?
>No not all and even those that do often do not do so on the same gear,
>links and peers as their unicast forwarding.
>> 2:  Is there any placeholder where one can get to know the
>> Multicast Internet Route table (usage, stability etc) just like
>> Unicast Route table (
>Marshall Eubanks at one time probably maintained the most comprehensive
>IP multicast status pages at (no
>longer available).  I've not seen nor heard from Marshall in a long
>time so I wouldn't expect this to come back any time soon.
>Sadly I don't know of any suitable replacement, but you might find some
>of that by searching here, if nothing else using the router proxies to
>examine status by hand:
>  <>
>CAIDA used to do some, but I'm not sure they have anything active any
>longer, browsing their tools and data may turn up some hints to other
>The once NLANR inspired and run Beacon project hasn't completely died
>out, there is this I found at for instance:
>  <>
>Interdomain IP multicast has practically since the beginning
>been a notoriously niche and limited service compared to unicast
>service.  There are a handful of reasons for that, but I think you will
>find it becoming decreasingly available rather than more so on
>interdomain basis.

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