Yahoo REST Web Service Authentication
All Yahoo API web services are free to consume at present. Once service consumers have signed up for an account with Yahoo, they are assigned an API Key/Application ID. When making a REST web service call the API Key must be included in the URL request.
Some Yahoo API web services use basic http authentication if a username and password is required, the Delicious API from Yahoo is an example. The http Authorization header is assigned the value of the base64 encoded username and password. A client with the following credentials:
username = MyUserName
password = MyPsswd
Places the username and password together to create the following string, which is then encoded using base64.
The resulting base64 encoded string is passed as a http header during the request, for example:
Authorization: Basic TXlVc2VyTmFtZTpNeVBzc3dk
The Delicious API also uses Secure Socket Layer (SSL) for transport level security, the https protocol is used instead of http when making a request. Some service providers use HTTP-Auth and SSL in combination.