Key features of the 1756-CNB module include:

ControlNet interface: The module has dual ControlNet ports (A and B) for connecting to the ControlNet network.

Redundancy support: It supports redundant network configurations for enhanced system reliability. Both ports can be used in redundant or ring configurations for fault tolerance.

Diagnostic indicators: The module has status indicators for power, network status, network activity, and fault conditions, providing diagnostic information for troubleshooting.

Configuration and management: The module can be configured and managed using Rockwell Automation's Studio 5000 software, which allows you to set up network parameters and monitor the module's status.

By using the 1756-CNB module in a ControlLogix system, you can integrate the ControlLogix controller into a larger ControlNet network, enabling communication with other devices and facilitating control and data exchange in an industrial automation environment.