How to use Authorization data invite command

I have been trying to use the Authorization Data Invite command (0x000B) but I have so far been unsuccessful. Can anyone help me with a usage example similar to authorization app example in the documentation?


Hi Ikechukwu,

For the Invite command you need to already have a Authorization-ID and a Shared Secret.
So either you already have it our you perform the Authorize app flow first.

Then you need to do the same flow as with the Unlock example, so first get a Challenge and with this Challenge and the Security-PIN you’re able to send the Invite command.




I have been trying to use Authorization Data (Invite) command, but I cannot finish it yet. Could anyone point me in the right direction?

What happens:

  • CL send Request data for Challenge to SL
  • SL returns Challenge in 5 indications
  • CL sends Authorization Data Invite command (0x000B)
  • SL returns another challenge in three indications -> ( command 0x0004 )

After sending the Authorization Data Invite command I was expecting that a new authorization entry would be created and authorization id of new entry would be returned in Authorization-ID (Invite) command.

Am I doing something wrong; what shall I do with second challenge?

Thank you,

Hi Lukas,

The SL does not send a second challenge after the CL sends the Authorization Data Invite command ()x0B). The second challenge is only issued when the CL sends the Authorization Data command (0x06) during app authorization. I have developed a Flutter library that implements the Authorization Data Invite command. You can view it here to see how the command works.


Hi Ikechukwu,

thank you, but I’m still not sure what I am doing wrong, I am sending the authorization invite command, not the standard one.

This is what the communication looks like -> all happens on Keyturner service USDIO, just like in your flutter project.

Communication below is in unencrypted state:

// CL requesting challenge
FF5C3400 0100 0400 D08E

// SL returns challenge:
FF5C3400 0400 F4416A22190D4104B99EA7D2E6C96252C48B98CD6765D2AC5F0A683BC95E48A0 FE84

//CL sends authorization data Invite command
FF5C3400 0B00 496E7669746554657374204D6F6269736F667400000000000000000000000000 00 DE831A576AA002F5BE4738062D85A043AC32378783CF6411D732DAF86E79CF8E 00 00 00000000000000 00000000000000 00 0000 0000 F4416A22190D4104B99EA7D2E6C96252C48B98CD6765D2AC5F0A683BC95E48A0 0457 C7CA

// SL returns the same challenge as before
FF5C3400 0400 F4416A22190D4104B99EA7D2E6C96252C48B98CD6765D2AC5F0A683BC95E48A0 FE84

Thank you,