The attributes in the Signing group are as follows:
This attribute specifies whether all SAML assertions will be digitally signed (XML DSIG) before being delivered. Selecting the check box enables this feature.
This attribute specifies whether all SAML requests will be digitally signed (XML DSIG) before being delivered. Selecting the check box enables this feature.
This attribute specifies whether all SAML responses will be digitally signed (XML DSIG) before being delivered. Selecting the check box enables this feature.
All SAML responses used by the Web Browser POST Profile are digitally signed whether or not this feature is enabled.