LTI Reference Implementation: Audience in Platform?

LTI Reference Implementation: Audience in Platform?

I'm confused about the Audience field in under Edit Platform in the Reference implementation.

Under the Third Party Initiated Login section, it states the iss field is: REQUIRED. The issuer identifier identifying the learning platform..

When I perform a launch to my tool from the reference implementation (where ref implementation is now the Platform), the iss field shows what is in the Audience field. As I understand it, the aud field should be the either:

  • The issuer_id for Tool originating messages
  • The client_id for Platform originating messages

So should that field really be named Issuer ID since it's actually populating the iss field? If that is the case, why would this field be editable as it would always be your current platform?


Any input here?

Anyone have any insight into this, or am I misunderstanding something?


Re: LTI Reference Implementation: Audience in Platform?

My understanding is that, for LTI messages, a platform inserts the client ID as the aud claim, and a tool inserts the platform ID as the aud claim. The aud claim should be an array, but is also permitted to be a simple string value if the array would otherwise only contain a single value. HTH.

jrissler's picture

That's a good find, that

That's a good find, that label would def be better as Issuer vs Audience.