Secure XML: The New Syntax for Signatures and Encryption

17.1. Algorithm Syntax

XML Security represents algorithms that it uses via an element with an Algorithm attribute. This attribute's value is a URI (see Chapter 7) that indicates the particular algorithm to use, whereas the element name indicates the role played by the algorithm.

Each algorithm has some implicit inputs or parameters, depending on its role. A list of such roles and their implicit inputs appears in Section 17.2.

Some algorithms also take explicit parameters provided by the element or text content of the algorithm role element, as specified for the particular algorithm. When using element content, parameter elements have algorithm- or role-specific names. These element content names must appear in the main namespace of the XML Digital ...