Control Network Newsletter
Understanding BASrouterLX Advanced Features
A BACnet router is used to route messages between BACnet/IP, BACnet Ethernet and BACnet MS/TP networks. The BACnet routers can also act as BBMD devices as well as provide BACnet/IP routing between two UDP ports. With its more powerful processor, the BASrouterLX has advanced features such as MS/TP Backbone, I-Am Broadcast Control, Allowlist option for enhanced security, MS/TP slave proxy support (allowing auto-discovery of MS/TP slaves) and MS/TP frame capture and storage for use with Wireshark®.
MS/TP Backbone: In most circumstances, BACnet routers are connected over a common Ethernet trunk integrating MS/TP devices. For scenarios where two routers are connected using MS/TP, this can cause communication issues between BACnet/IP devices. If the BACnet client and the end device both communicate via BACnet/IP (Ethernet) with intervening MS/TP networks, then the client and end device may try to send larger messages than MS/TP can carry because they think communication is occurring over Ethernet using 1500-byte messages. MS/TP networks cannot accommodate these larger messages which will be dropped. With the MS/TP backbone feature enabled, the BASrouterLX will notify the BACnet/IP messages to use a smaller packet size so it can traverse over MS/TP networks.
I-Am Broadcast Control: Most of the MS/TP server devices use a low-power CPU and only need to respond to requests from the BACnet client. They usually don't need to receive all the I-AM messages from other devices in response to a Broadcast Who-Is message. To prevent MS/TP devices from being inundated with Broadcast I-AM messages, the BASrouterLX I-AM Broadcast Control feature can be enabled.
Allowlist: You can indicate which IP devices can communicate through the BASrouterLX to the MS/TP network. Generally, any BACnet client can access any point on any device. The allowlist can control which BACnet/IP clients can discover and read/write points on the MS/TP devices. Up to 10 IP addresses can be entered into the BASrouterLX Allowlist.
MS/TP Slave Proxy: MS/TP slave device with MAC address greater than 127 cannot participate in token passing and need a proxy device to communicate with the slave device and deliver its data to the BACnet network. The BASrouterLX supports the MS/TP Slave Proxy feature allowing it to integrate MS/TP slave devices into the BACnet network.
Wireshark capture: The BASrouterLX has a webpage that allows the traffic capture of the MS/TP network. The captured file can then be clicked and viewed on the local PC using Wireshark. This allows easy troubleshooting of the MS/TP network as long as the BASrouterLX is accessible via its webpage.
To learn more, visit the BASrouterLX product page.