Technical data

Fieldbus Communication • 213

BACnet/IP

WAGO-I/O-SYSTEM 750

BACnet/IP Controller

4.2.1.6.2.2 BACnet/IP in Foreign Networks

If a device is connected to one subnet and would like to receive broadcasts

from another subnet or send to another subnet, BBMDs are required in both

subnets (see Fig. 4-4).

For a device to communicate that does not have a BBMD in its own

(sub)network and therefore becomes a Foreign Device (FD), the other

BACnet/IP (sub)networks must have BBMD/FDs (see Fig. 4-5). The foreign

devices register with this BBMD/FD using their IP addresses. In this way,

broadcasts from other subnets can be received or can be sent to these net-

works.

router

Internet

BBMD/FD

BACnet

device

BBMD/FD

BACnet device

BACnet

device

Network 1 Network 2

Foreign device

1.Registration

2.Unicast to BBMD/FD

3.Transforming/sending as broadcast

Fig. 4-5: Registration of a foreign device G083011d