What NM-FDR-A Is
NM-FDR-A (Network Management-Foreign Device Registration-A) is the BACnet Interoperability Building Block (BIBB) for a device that registers itself into a remote BACnet BBMD’s Foreign Device Table (FDT), so it can participate in that BBMD’s broadcast traffic without a BBMD of its own. A device claiming NM-FDR-A is the initiating side; the BBMD accepting the registration is claiming NM-BBMDC-B.
What It Requires
| Piece | What it does |
|---|---|
| Registration request | Sent to a target BBMD’s address, naming a time-to-live for the registration |
| Renewal | The registering device re-sends the request before the time-to-live expires, or the BBMD drops it from the FDT |
| Address configuration | The device needs the BBMD’s reachable address, which behind NAT (Network Address Translation) means the BBMD’s public address, not a private one |
Where You Meet It in the Field
A remote workstation over VPN, a diagnostic laptop on a temporary connection, or any single device that needs broadcast visibility into an existing BACnet/IP subnet without justifying a full BBMD of its own is claiming NM-FDR-A. The deployment-pattern comparison covers when this fits better than a mesh of BBMDs.
What Chipkin Provides
The CAS BACnet Stack supports NM-FDR-A today, evidenced by a dedicated test panel rather than a BTL profile run. Talk to us about your specific remote-access scenario.