v4/v6 Domain Name Conversion. This method, originally
proposed in [23], is similar to the technique used to provide
virtual hosting service in HTTP 1.1, which makes it possible to support multiple websites on the same web server, sharing the
same IPv4 address, by exploiting the information contained in
the HTTP Host header to identify the specific web site requested
by the user. Similarly, it is possible to program the DNS servers in
such a way that, upon a DNS request for the domain name of an
IoT web service, the DNS returns the IPv4 address of an HTTPCoAP
cross proxy to be contacted to access the IoT node. Once
addressed by an HTTP request, the proxy requires the resolution
of the domain name contained in the HTTP Host header to the
IPv6 DNS server, which replies with the IPv6 address that
identifies the final IoT node involved in the request. The proxy
can then forward the HTTP message to the intended IoT via
CoAP.