Industrial estates are full of equipment that predates Ethernet: meters and controllers speaking Modbus over RS485, devices with RS232 consoles, panels wired for contact-closure signaling. The RUT956 exists for exactly this world. Alongside its cellular WAN it carries RS232 and RS485 serial ports, GNSS for location, and configurable inputs and outputs — the full toolkit for turning a legacy cabinet into a connected site. The connectivity core is Teltonika's proven dual-SIM design: Cat 4 LTE with two SIM slots and automatic failover, so remote and unmanned installations do not depend on a single carrier's network. Ethernet ports and 802.11b/g/n Wi-Fi handle modern IP devices and commissioning access, while wired-WAN failover lets the router arbitrate between a site circuit and its cellular paths. RutOS ties the I/O story together. Serial gateway functions bridge RS232/RS485 equipment to IP protocols for SCADA backhaul; VPN support secures the path to control centers; the integrated firewall and access policy protect OT devices that were never designed for exposure. GNSS adds timestamped location for mobile and dispersed assets, and the I/O lines integrate alarms and actuation. Fleet operations run through Teltonika RMS. Deploy the RUT956 for utility telemetry, pump and lift stations, energy sites, and any retrofit where serial equipment, environmental signals, and cellular WAN meet in one enclosure.