The IBET radio system, shared between rcmp , us border patrol, and both us and canadian customs.
i have a lengthy info article on it, if you want to private ,msg me.
THEY actually have a body (board) that maintains and implements the system, made up
of canadian and us officials.
They used to have interoperability issues in the past, but for the most part this has bern fixed.
This means the connection between the current canadian agency radios rcmp, customs, canadian coast guard with that of us border patrol radio system, customs, and us coast guard.
These radio systems are encrypted, p25. And most comms you will be lucky to hear in the clear is when a us border patrol connects interopt to a county sherrif or state patrol on a non encypted radio system by interopt patch.
rcmp radio system has talkgroups, for interoperability, between can and us systems. So the usbp, and rcmp would communicate on a system with a tg or channel designated for that specific reason between the 2 agencies.