This API uses basic webforms authentication. To authenticate a user prior to calling a method, you will need to add a standard HTTP authorization header to the request.
This will require the username and password, separated by a colon(:) and Base64 encoded.
Here is an example:
Authorization header: Basic ZGVtb0BwYXN0ZWxteW1vbmV5LmNvLnphOlBhc3N3b3JkMTIz