nRF Thread Topology Monitor overview

The status indicator to the right of the Select serial port drop-down list shows the connection status of the selected device. The indicator is green when nRF Thread Topology Monitor has established connection to the device.

The Discovered devices panel allows you to customize the topology scanning process. For example, you can narrow the scanning to display only a selection of network devices. You have the following actions available at start-up:

• Start scan initiates the scanning for network devices. After the Thread network topology is displayed in the Topology panel, this button changes to Stop scan, which interrupts the scanning for network devices and clears the Topology panel.
• Clear resets the scanning results.
• Configuration drop-down menu allows you to define Thread network parameters for scanning. Because nRF devices act as OpenThread CLI devices, you must configure several parameters before scanning, as described in Connecting to a Thread topology.
  Figure 4. Configuration drop-down list

  
  The following basic Operational Dataset parameters must be configured before scanning:

  Radio channel

  This parameter specifies the radio channel used by the Thread network. The list allows to select a value from 11 to 26 (inclusive).

  Network PAN ID (in hex)

  This parameter specifies the PAN ID of the Thread network in the hexadecimal format. For example, abcd for 0xabcd, which is also the default value.

  Network Master Key (in hex)

  This parameter specifies the master key used for authenticating a device into the Thread network. It is provided in the 32-byte format, for example 00112233445566778899aabbccddeeff, which is also the default value.

  The following Polling Parameters are optional when configuring the scanning:

  Polling interval

  This parameter specifies how often an nRF device polls other nodes for information about their status.

  Note: Keep the polling interval bigger (in seconds) than the total number of routers in the network.

  Timeout time

  This parameter specifies the maximum time span between two responses to poll requests, after which the node is removed from the network topology.

Additionally, you can select the Perform factory reset option either to complete a factory reset before the attachment process or to use normal reset. Selecting this option has the following effects:

• It allows an nRF Thread device to change its Operational Dataset parameters.
• It forces a random choice of a new Extended Address during the factory reset procedure. The application will ignore any custom or previously assigned label.

After you restart the application with the Perform factory reset option, the topology will disappear and reappear after up to two minutes. This is because an nRF Thread device connected to the Thread Topology Monitor must become a Thread Router to obtain all routing information. In the Thread protocol, only the Leader of the network can allow a Child to become a Thread Router. If the Leader has been restarted and some other Thread Routers exist in the network, they need to time out the previous Leader and elect a new one.

The Device parameters panel lists information about the currently selected device and allows you to interact with it. When you select a device, the following information is updated in the Device parameters panel:

• Extended Address displays the address of the device in the hexadecimal format.
• Short Address displays the shortened address of the device, with Child and Router IDs.
• Device Name displays the custom device name.

You can also use the following options in this section:

• Ping/Identify sends a ping to the Thread device that you select in the topology panel.
  Note: If the Thread device uses the Thread BSP module, LEDs on this device start blinking.
• Refresh updates information about the device before regular polling.
• Change Name allows you to modify the device name in the application.
  Note: nRF Thread Topology Monitor matches Extended Address with Device Name and stores it in the persistent memory on the PC.

The Log panel allows you to view the most important log events for the current nRF Thread Topology Monitor session. The events are tagged with a timestamp.

The topology panel is initially empty. After the discovery of Thread nodes, it is populated with visual representations of the nodes and connections between them.

While the visual representation of each node in the topology view is identical regardless of the hardware you are using, the following color schemes are used for the Thread icon of each node type:

• Orange Thread icon represents the Leader device.
• Blue Thread icons represent Routers.
• Black Thread icons represent End Devices.

Moreover, connections are dotted with arrows to indicate one of the following communication link types:

• Router-to-router - indicated by two arrows in opposite directions.
• Router-to-end-device - indicated by one arrow. End Devices communicate through a single router and cannot forward packets for other network nodes.

You can interact with the topology nodes in the following ways:

• Use the mouse scroll to zoom in and zoom out of the network topology.
• Press the left mouse button and move the mouse around to move the network topology in the same direction.
• Click a node to select it and drag it to a different location within the topology view while keeping the left mouse button pressed.
• Click a node to see its particular connections, which will appear as bolded out in the topology view upon selection.
• Click a node to see its parameters in the Device parameters panel.
• After selecting a node, modify the device name label or ping the device using options in the Device parameters panel. See Device parameters for more information.