Confirming source-routed multicast is dead on the public Internet

Adam Davenport adam at
Wed Aug 1 15:45:44 UTC 2018

I can confirm that GTT does indeed filter IP sourced from at its edge.

On 7/31/2018 6:44 PM, Patrick W. Gilmore wrote:
> It is hard to prove a negative.
> So let’s prove a positive. One of the largest (2nd largest?) transit networks on the planet just affirmatively stated they filter at their border. It is now possible to state that multicast is not ubiquitous on the Internet.
> If any other large transit network (L3, GTT, HE, Cogent, etc.) would like to confirm they filter at their borders as well, that would put the final nail in the coffin.

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