Networking requirements for RCUs

Each Mount Kelvin 401-D RCU needs a working internet connection via ethernet. This means an ethernet connection is required in each room, usually in the electrical cabinet of the room. RCUs require outbound connectivity to the internet and the network connection must be installed and fully functional in order to commission the system.

Internet connection

The connection between the Mount Kelvin 401-D RCUs and cloud backend is built upon WebSockets. Monitoring of RCU connection status is handled by monitoring the WebSocket state. In addition to the socket to the command&control backend, a separate fleet management system monitors the RCUs.

RCUs acquire IP addresses via DHCP and no manual IP assignment is needed. All RCUs in a single installation must be placed in a single network, which does not filter mDNS traffic. In a typical network, no firewall changes are necessary, but if a firewall with outbound communications restrictions is present, the following ports must be open:

Firewall ports

HTTPS to cloud backend, system updates
Logging service for maintenance
NTP time synchronization
DNS (Domain Name Service)

No inbound connections are needed.

Bandwidth requirements and latency

The bandwidth requirements of the RCUs are relatively low, a few hundred MB / month.

A more critical consideration is network latency, but this aspect is only relevant when using the mobile or web application to control the system and during commissioning. During normal operation, the switches and sensors in the rooms are used as the primary control mechanism and the network connection is mostly used for status reporting and monitoring. Temporary spikes in network usage may be observed during updates of the RCU software, which can amount to 1-2Gb per RCU.

Other devices, such as building automation systems may be present in the same network as RCUs, however, we recommend separating staff and guest networks to ensure that a reasonable amount of bandwidth remains available for room control.


  1. All 401-D RCUs are connected to the electrical cabinet with their own individual cables
  2. All 401-D RCUs are successfully connected to the internet
  3. All 401-D RCUs have DHCP connection (fixed IP addresses are not required)
  4. There is no MDNS filtering in the network
  5. If a firewall has restrictions for outgoing data, the aforementioned firewall ports are open