Handler
The <Handler>
 element is used to configure generic SP handlers that offer miscellaneous functionality that doesn't fall into the categories covered by other predefined elements.
Typically, if a handler implements a SSO protocol, issues SSO requests, deals with logout, or implements other capabilities baked into the SAML 2.0 specification, it will not use the generic element to configure itself.
Handler types
Handlers are specified via the type=
attribute. They have individual attributes and child elements, as well as the Common Attributes listed below. The following are available
Metadata Generation  Handler
Status Handler
Session Handler
Discovery Feed Handler
Attribute Checker  Handler
External Authentication Handler
Attribute Resolver Handler