Example integrated Metasys BACnet/IP network - Metasys - LIT-12012458 - Field Device - 13.0

Metasys IP Networks for BACnet/IP Controllers Technical Bulletin

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Figure 1 illustrates an Integrated Metasys BACnet/IP network consisting of three network engine s, each supervising 200 Metasys BACnet/IP devices. In this example, the IT department has allocated VLANs 10 through 12 and the following three /24 subnetworks for the BAS network:
  • VLAN 10:
  • VLAN 11:
  • VLAN 12:
Figure 1. Integrated Metasys BACnet/IP network - example

Table 1 shows the recommended IP address assignments for the devices in each of the VLANs. In this type of network, IT configures the switches in the distribution and access layers (the access layer has the switches to which the IP-based controllers connect to the network). For the example in the following table, it is assumed that IT configured the access-layer switches so that the SVI/default gateway has the lowest IP address in the subnetwork. It is also assumed that IT configured the corresponding SVIs in the distribution-layer switches. Such a configuration allows for routing between the access-layer switches without additional explicit configuration of IP routing.

Table 1. Recommended IP Address Assignments - Integrated Network Example

SVI/default gateway

IP controllers

Network engine


Determined by IT -


Determined by IT -


Determined by IT -

In addition to the IP address allocations/assignments for the BAS VLANs in Table 1, the IT department would need to:
  • assign the switch ports to the same VLAN as the devices physically connected to the port
  • configure the appropriate routes to ensure traffic can reach the BAS subnetworks
If a remotely located Metasys BACnet/IP device is to be connected to the network, it can be connected to any general purpose VLAN in the IT network and assigned an IP address from the subnetwork hosted by that VLAN. However, the remotely located device must be deployed with a BBMD in the same general purpose VLAN so that the remotely located device can be discovered by one of the network engine s in VLAN 10, 11, or 12. The BBMD must have a static IP assigned within the subnetwork hosted by the VLAN.
Note: BBMD configuration in Metasys is out of scope for this document.