Enroll a signature authentication method.

Enroll one or more instances of a signature-based authentication method.

Authentication method enrollments are associated with a user ('owner') and an authenticator ('authenticatorId') which are both identified through the access token. The authenticator ID must be signed to help verify the public key. Provide the signature in the enrollment request by using the 'signedData' attribute.

You can enroll multiple instances of a signature methodType in a single request but you cannot enroll more than one instance of the subType per authenticatorId. The response payload will indicate which enrollment requests failed and succeeded.

- verifyAuthenticator (Use IBM Verify.)