issue httpwg#418

Discovery about the support for HTTP2 during the domain name resolution.

draft-ietf-httpbis-http2.xml

@@ -318,7 +318,18 @@
           encouraged to coordinate their experiments on the ietf-http-wg@w3.org mailing list.
         </t>
       </section>
-
+	  <section anchor="discover-domain-http2" title="Dynamic discovery of the support for HTTP/2">
+        <t>	
+          A client that makes a request to a resource resolves the domain name before establishing the TCP connection with the server.
+        </t>
+        <t>
+          A client connected to an enterprise network previously determines the domain name of the local server or of the enterprise forward-proxy. This lookup is dynamic. It is made, as an example, with a call to the function FindProxyForURL() of the proxy.pac file discovered dynamically with DNS WPAD. 
+        </t>
+        <t>
+          The knowledge about the support for HTTP2 may be learned dynamically during the resolution of the actual domain name. DNS SRV is an available solution for discovering dynamically the support for HTTP/2. The SRV record provides the client with the host and port of a server which supports HTTP2 (e.g. _h2-10._tcp.example.com 3600 IN SRV 0 33 9876 h2srv.example.com). The support about HTTP2 for a server is valid only for the duration given by the Time To Live of the DNS SRV record.
+        </t>
+
+      </section>	  
       <section anchor="discover-http" title="Starting HTTP/2 for &quot;http&quot; URIs">
         <t>
           A client that makes a request to an "http" URI without prior knowledge about support for