<S:Envelope xmlns:S="http://schemas.xmlsoap.org/soap/envelope/">
  <S:Body>
    <samlp:AuthnRequest 
        xmlns:samlp="urn:oasis:names:tc:SAML:2.0:protocol"
        AssertionConsumerServiceURL="https://bwlp-masterserver.ruf.uni-freiburg.de/Shibboleth.sso/SAML2/ECP"
        ID="%REQUESTID%"
        IssueInstant="%TIMESTAMP%"
        ProtocolBinding="urn:oasis:names:tc:SAML:2.0:bindings:PAOS"
        Version="2.0">
      <saml:Issuer xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion">https://bwlp-masterserver.ruf.uni-freiburg.de/shibboleth</saml:Issuer>
      <samlp:NameIDPolicy AllowCreate="1"/>
    </samlp:AuthnRequest>
  </S:Body>
</S:Envelope>