Get Live Streaming from an Onvif Network IP Camera?

I have a network IP camera (Canon VB-M40). This camera supports ONVIF protocol. I implement its ONVIF functionality in windows using the C language. I got my RTSP URI using the following query.

snprintf(postData, sizeof(postData),
      "<?xml version=\"1.0\" encoding=\"utf-8\"?>"
      "<soap:Envelope xmlns:soap=\"http://www.w3.org/2003/05/soap-envelope\" "
      "xmlns:tds=\"http://www.onvif.org/ver10/media/wsdl\""
      "xmlns:tt=\"http://www.onvif.org/ver10/schema\">"             
      "<soap:Body>"
      "<tds:GetStreamUri>"
        "<tds:StreamSetup>"
          "<tt:Stream>0</tt:Stream>" 
          "<tt:Transport>" 
            "<tt:Protocol>HTTP</tt:Protocol>" 
          "</tt:Transport>"
        "</tds:StreamSetup>"
        "<tds:ProfileToken>profile1</tds:ProfileToken>"
      "</tds:GetStreamUri>"
        "</soap:Body></soap:Envelope>",
      username, digest_str, nonce_str, time_str); 

and the answer is:

<?xml version="1.0" encoding="UTF-8"?>
<SOAP-ENV:Envelope  xmlns:SOAP-ENV="http://www.w3.org/2003/05/soap-envelope" 
                    xmlns:SOAP-ENC="http://www.w3.org/2003/05/soap-encoding" 
                    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
                    xmlns:xsd="http://www.w3.org/2001/XMLSchema" 
                    xmlns:wsa5="http://www.w3.org/2005/08/addressing" 
                    xmlns:c14n="http://www.w3.org/2001/10/xml-exc-c14n#" 
                    xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd" 
                    xmlns:ds="http://www.w3.org/2000/09/xmldsig#" 
                    xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd" 
                    xmlns:MC2="http://www.onvif.org/ver10/schema" 
                    xmlns:MC3="http://www.w3.org/2005/05/xmlmime" 
                    xmlns:MC4="http://docs.oasis-open.org/wsn/b-2" 
                    xmlns:MC10="http://www.w3.org/2004/08/xop/include" 
                    xmlns:MC5="http://docs.oasis-open.org/wsrf/bf-2" 
                    xmlns:MC6="http://docs.oasis-open.org/wsn/t-1" 
                    xmlns:CC="http://www.canon.com/ns/networkcamera/onvif/va/schema" 
                    xmlns:MC1="http://www.onvif.org/ver10/media/wsdl" 
                    xmlns:MC8="http://www.onvif.org/ver20/analytics/wsdl/RuleEngineBinding" 
                    xmlns:MC9="http://www.onvif.org/ver20/analytics/wsdl/AnalyticsEngineBinding" 
                    xmlns:MC7="http://www.onvif.org/ver20/analytics/wsdl" 
                    xmlns:ter="http://www.onvif.org/ver10/error" 
                    xmlns:wsnt="http://docs.oasis-open.org/wsn/b-2" 
                    xmlns:tns1="http://www.onvif.org/ver10/topics">
    <SOAP-ENV:Header></SOAP-ENV:Header>
    <SOAP-ENV:Body>
        <MC1:GetStreamUriResponse>
            <MC1:MediaUri>
                <MC2:Uri>rtsp://192.168.5.53:8090/profile1=r</MC2:Uri>
                <MC2:InvalidAfterConnect>false</MC2:InvalidAfterConnect>
                <MC2:InvalidAfterReboot>true</MC2:InvalidAfterReboot>
                <MC2:Timeout>PT0M0S</MC2:Timeout>
            </MC1:MediaUri>
        </MC1:GetStreamUriResponse>
    </SOAP-ENV:Body>
</SOAP-ENV:Envelope>

according to the ONVIF specification, as soon as I get the stream URI, I have to send a DESCRIBE request to the device. I use this procedure because I need a stream over TCP.

My question is how to send a DESCRIBE request to the device and to which socket?

Should I send this request to the same socket to which I sent the GetStreamURI request. Or should I create another. And what will the request format be?