BB2-7030 User Guide – Rev. 1.0
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It important that only one device on an IP subnet be configured for BBMD. It is also important
that all but one device be configured to register with the one device in the middle, and that the
device in the middle is not configured to register with another BBMD.
If you do allow a BBMD device to both register and receive foreign registrations (registrations
from other BBMD devices), it will be important to set the hop counts low because broadcast
messages will echo back and forth repeatedly.
You can use a generic broadband router with port forwarding to give a BB2-7030 access to
Internet or WAN for building a large network spread across multiple buildings. When BBMD is
used to refer to other BBMD’s that are connected via broadband router, the IP address must be
the external IP address of the broadband router. The broadband router’s port forwarding table
should open port 0xBAC0 (47808) for UDP. The internal IP address will be the LAN address of
the BB2-7030. In the screen image below, the BB2-7030 is configured for an IP address of
192.168.1.100. Externally, it is referred to as 173.11.33.51 in the network diagram that follows.
IMPORTANT: The broadband port forwarding example shown below is a non-secured
connection. While functional, if you will be using open Internet as your primary connection for a
real world application, you should consider using a Broadband VPN router with firewall instead.
These are available with AES encryption for as little as $100. Our non-secured test case used a
D-Link EBR-2310. Our secured VPN test case (which follows) used a D-Link DIR-130.
NOTE: In order for BBMD to work via port forwarding, it will be necessary to have an Internet
connection with a Static IP address. If your Internet connection uses your ISP’s DHCP to get an
address, it is not suitable for BACnet via WAN use. If you are serious about BACnet over WAN,
you probably need to get your IT people involved.
