External Thread Commissioning

OpenThread Border Router (OTBR) features a Thread Border Agent, which supports external Thread Commissioning. In external Thread Commissioning, a device outside of the Thread network (for example, a mobile phone) commissions new devices onto the network.

The Thread Commissioner serves to authenticate a user (external Commissioner) or a Thread device onto the Thread network. After authentication, the Commissioner instructs the Border Router to transfer Thread network credentials, such as the master key, to the device directly.

This is an example of in-band commissioning, where Thread network credentials are transferred between devices over the radio.

Key Point: During commissioning, the Thread Commissioner never gains possession of the network master key.

This guide details how to commission an OpenThread device onto a network created and managed by the OTBR Web GUI, using one of the following external Commissioners:

• OT Commissioner CLI
• OT Commissioner App for Android
• Thread Commissioning App for Android

To learn how to commission without an external Commissioner, see Thread Commissioning.

Select Commissioner type

Use the buttons to filter this guide based on Commissioner type:

OT Commissioner CLI OT Commissioner Android App Thread Group Android App

Selected: OT Commissioner Android App

Form the Thread network

Web GUI

The recommended way to form a Thread network is via the OTBR Web GUI. When doing so, change all the default values on the Form menu option, except for the On-Mesh Prefix.

Make note of the Passphrase used. This passphrase is the Commissioner Credential and is used (along with the Extended PAN ID and Network Name) to generate the Pre-Shared Key for the Commissioner (PSKc). The PSKc is needed to authenticate the Thread Commissioner (the external device) to the network.

Note: The Commissioner Credential is a user-defined string between 6 and 255 characters, UTF-8 encoded.

Manual

The Thread network can also be formed manually on the command line of OpenThread POSIX, using ot-ctl.

1. Initialize a new operational dataset:

   sudo ot-ctl dataset init new
   Done
   

2. Set the network credentials:

   sudo ot-ctl dataset panid 0xdead
   Done
   

   sudo ot-ctl dataset extpanid dead1111dead2222
   Done
   

   sudo ot-ctl dataset networkname OpenThreadGuide
   Done
   

   sudo ot-ctl dataset masterkey 11112233445566778899DEAD1111DEAD
   Done
   

3. Generate a hex-encoded PSKc by using a Passphrase (Commissioner Credential), the Extended PAN ID, and the Network Name with the PSKc Generator tool on the OTBR. Make sure to use the same Extended PAN ID and Network Name that was used in the operational dataset:

   cd ~/ot-br-posix/build/otbr/tools
   ./pskc J01NME DEAD1111DEAD2222 OpenThreadGuide
   198886f519a8fd7c981fee95d72f4ba7

4. Set the PSKc:

   sudo ot-ctl dataset pskc 198886f519a8fd7c981fee95d72f4ba7
   Done
   

5. Commit the active dataset, set the on-mesh prefix, and form the Thread network:

   sudo ot-ctl dataset commit active
   Done
   

   sudo ot-ctl prefix add fd11:22::/64 pasor
   Done
   

   sudo ot-ctl ifconfig up
   Done
   

   sudo ot-ctl thread start
   Done
   

   sudo ot-ctl netdata register
   Done
   

6. Confirm the network configuration:

   sudo ot-ctl state
   leader
   Done
   

   sudo ot-ctl pskc
   198886f519a8fd7c981fee95d72f4ba7
   Done
   

Prepare the Joiner device

Build and flash a device with OpenThread, to function as the Joiner. For an overview of building OpenThread, see the Building Guide.

Use the JOINER=1 build switch to enable the Joiner role.

For example, to build the CC2538 example platform for use as a Joiner:

make -f examples/Makefile-cc2538 JOINER=1

Specific instructions on building supported platforms with GNU Autotools can be found in each example's platform folder/examples/platforms).

Once the Joiner device is ready, obtain its factory-assigned IEEE EUI-64. Use the eui64 command in the OpenThread CLI:

eui64
0000b57fffe15d68
Done

Download the app

External commissioning is supported by the OT Commissioner Android App, available for download at the and building on the GitHub repository. Follow the instructions in the README to build and install the app on an Android device..

Note: The OT Commissioner Android App is only available for Android.

Connect to the Border Router

1. Connect the device with the OT Commissioner Android App to the Wi-Fi access point on the Border Router.
2. Open the OT Commissioner Android App and select the desired Border Router from the available list. The name is the same as the Thread network created by the OTBR Web GUI. If the same Border Router shows up multiple times with different IPv4 and IPv6 addresses, select the one with the static IPv4 address used for the Wi-Fi access point setup.
3. Enter the Passphrase (Commissioner Credential) set in the OTBR Web GUI (and used to generate the PSKc) when prompted for a password.

Commission the Joiner

Once connected to the Border Router, the app provides the option to scan a Connect QR Code or enter a Join Passphrase manually. The Join Passphrase is also called the Joiner Credential, and is used (along with the Extended PAN ID and Network Name) to generate the Pre-Shared Key for the Device (PSKd). The PSKd is then used to authenticate a device during Thread Commissioning. The Joiner Credential should be unique to each device.

Thread Connect QR Codes are created with the following text string format:

v=1&&eui=0000b57fffe15d68&&cc=J01NU5

Where eui is the Joiner device's EUI64 value and cc is the Joiner Credential. Use this text string with an online QR Code generator to create a QR Code for scanning.

Note: The Joiner Credential is a device-specific string of all uppercase alphanumeric characters (0-9 and A-Y, excluding I, O, Q and Z for readability), with a length between 6 and 32 characters.

1. In the OT Commissioner Android App, scan the Connect QR Code of the Joiner device, or enter the EUI64 and Joiner Credential manually. This generates the PSKd, propagates the steering data through the Thread network, and establishes a DTLS session.
2. While the app is waiting, enter the OpenThread CLI on the Joiner device and start the Joiner role with that same Joiner Credential:

   ifconfig up
   Done
   joiner start J01NU5
   Done

3. Wait a minute for the DTLS handshake to complete between the Commissioner and Joiner:
   

   
   Join success!

4. The OT Commissioner Android App also updates with an "Commission Succeed" confirmation message.

The Joiner has obtained the Thread network credentials, and can now join the network.

Join the network

On the Joiner device, start the Thread protocol to automatically join the network.

thread start
Done

Check the state after a few moments to confirm. It may initially start as a child, but within two minutes it should upgrade to a router.

state
router
Done

Also check the device's IPv6 addresses. It should have a Global address using the On-Mesh Prefix specified during formation of the Thread network through the OTBR Web GUI.

ipaddr
fdde:ad11:11de:0:0:ff:fe00:9400
fd11:22:0:0:3a15:3211:2723:dbe1
fe80:0:0:0:6006:41ca:c822:c337
fdde:ad11:11de:0:ed8c:1681:24c4:3562

Ping the external internet

Test the connectivity between the Joiner device in the Thread network and the external internet by pinging a public IPv4 address.

For example, the Well-Known NAT64 prefix of 64:ff9b::/96 and an IPv4 address of 8.8.8.8 combine to form an IPv6 address of 64:ff9b::808:808.

Add an external route for the NAT64 Prefix:

sudo ot-ctl route add 64:ff9b::/96 s med
Done
sudo ot-ctl netdata register
Done

Ping the synthesized IPv6 address 64:ff9b::808:808 from the OpenThread CLI on the Joiner device:

ping 64:ff9b::808:808
16 bytes from 64:ff9b:0:0:0:0:808:808: icmp_seq=3 hlim=45 time=72ms