BACnet/IP breaks because the source address is changed as it goes through the NAT-Router. If there's only one device behind the NAT then you can set up port forwarding, but that's not a great solution. You can use a set of Annex-H half routers, which essentially tunnels the traffic over IP. I'd be happy to help you with that, it would make a good use-case for the BFR documentation.
BTW, sorry for taking so long to respond, somehow I don't get notified when there are forum posts and I have to fix that.
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We are trying to do BACnet over a VPN to a third party and I am being told that BACnet breaks if you try to NAT or PAT it. Is this true?
BACnet/IP breaks because the source address is changed as it goes through the NAT-Router. If there's only one device behind the NAT then you can set up port forwarding, but that's not a great solution. You can use a set of Annex-H half routers, which essentially tunnels the traffic over IP. I'd be happy to help you with that, it would make a good use-case for the BFR documentation.
BTW, sorry for taking so long to respond, somehow I don't get notified when there are forum posts and I have to fix that.