The topics in this section describe how the Product Advertising API authenticates your requests. In this section you can learn about the basics of authentication, how your AWS account and identifiers are used to support authentication, and how to create an HMAC-SHA1 signature. This section also covers the request authentication requirements for Query and SOAP requests.

	Important
	You have until August 15, 2009 to authenticate requests sent to the Product Advertising API. After August 15, 2009, messages that aren't authenticated will be denied.