Basic authentication refers to how the API credentials are passed over from the client to the server. Basic auth supports both username/passwords and username/token combinations. To toggle between password-based and token-based authentication, "/token" will need to be appended to your username and then the token inputted as the password. The screenshot below is using the Rest API web service layout with a token:
A similar setup works via curl to test the setup with Basic auth and a token outside of Assure:
curl https://someserver.infogix.com/api/v2/example/endpoint/ -u "username_removed@infogix.com/token:TOKEN_REMOVED"