A series of nested boxes shows the SOAP envelope containing two boxes labeled SOAP envelope header and SOAP envelope body. Within the header, there is a box labeled WS-Security header that contains two boxes labeled SAML Assertion and Digital Signature. Within the SOAP envelope body is a box labeled Business Payload. There is an arrow from the Digital Signature box to the SAML Assertion box, and from the Digital Signature box to the SOAP envelope body.