SAML 2.0 HTTP POST Binding : AuthnRequest Signature

Hi All,

Please help me to understand how to send the AuthnRequest message's signature with HTTP POST binding. I went through the specs but I was unable to find exact information on the subject. I know for HTTP Redirect Binding we can use the Deflate encoding and send the signature as a query string parameter named "Signature". What is the mechanism for HTTP POST biding ? Do we send the signature as a hidden field ? 

I did some Google search as well but I could not get a proper answer. I really appreciate your help.

Thanks,

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Suresh Attanayake

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