As per above, is it possible to send packets to a multicast address e.g 220.127.116.11 on a port number, over a VPN?
Technically yes, but you might need some Multicast routing protocols to assist. PIM etc.
Gets complex if its not on the same broadcast domain/subnet.
Hi, you may need to first pack it in GRE then shred that through IPSec to get multicast to work, and obviously PIM or Multicast Proxy may/will be required depending on a few aspects.
there is a few windows applications that push multicast over VPN too, designed for exactly this purpose.
Came out of the hamachi etc days, where sometimes "LAN" Games wouldn't work over it because it was announcing over multicast and iver not flowing, or flowing out the wrong interface (which is where interface metrics also come into it)
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