There already is a SRV service name reservation for both http and www-http, with Tim Berners-Lee as the contact name. Fun fact: using DNS address records ("A"

There already is a SRV service name reservation for both http and www-http, with Tim Berners-Lee as the contact name. Fun fact: using DNS address records ("A" or "AAAA") for endpoint name resolution in HTTP is a convention; it is not required in the standard or in any of the normative references. Web services do not own the address record and should never have been using it in the first place. Nonetheless they continue squatting addresses in a de facto assertion of unwarranted privilege, and every other use of the DNS has to steer carefully around. When SRV is discussed e.g. on the HTTP/2 list, the objections of resolution speed and number of round-trips are usually raised. But SRV records do not intrinsically require an additional lookup or round trip. Unoptimised zone configurations (especially those that slice at _tcp, which occurs at some Microsoft shops) may fare less well, but that is true of all DNS configuration. Services that care about resolution speed already optimise their DNS as necessary, and they would for SRV as well if it were mandated. In practice, the reasons for non-adoption are, mundanely, simply a matter of inertia, combined with a lack of motivation: the browser vendors who in practice write the HTTP standard do not care to change and have no external force that will push them off overloading the address record.