First published on Biz2, 10/00
The Domain Name System is coming apart at the seams. DNS, the protocol which maps IP addresses like 206.107.251.22 to domain names like FindDentist.com, is showing its age after almost 20 years. It has proved unable to adapt to dynamic internet addresses, to the number of new services being offered, and particularly to the needs of end users, who are increasingly using their PCs to serve files, host
software, and even search for extra-terrestrial intelligence. As these PCs become a vital part of the internet infrastructure, they need real addresses just as surely as yahoo.com does. This is something the DNS system can’t offer them, but the competitors to DNS can.
The original DNS system was invented, back in the early 80s, for distinctly machine-centric world. Internet-connected computers were rare, occupying a few well-understood niches in academic and government labs. This was a world of permanence: any given computer would always have one and only one IP address, and any given IP address would have one and only one domain name. Neat and tidy and static.
Then along came 1994, the Year of the Web, when the demand for connecting PCs directly to the internet grew so quickly that the IP namespace — the total number of addresses — was too small to meet the demand. In response, the ISPs began doling out temporary IP addresses on an as-needed basis, which kept PCs out of the domain name system: no permanent IP, no domain name. This wasn’t a problem in the mid-90s — PCs were so bad, and modem connections so intermittent, that no one really thought of giving PCs their own domain names.
Over the last 5 years, though, cheap PC hardware has gotten quite good, operating systems have gotten distinctively less flaky, and connectivity via LAN, DSL and cable have given us acceptable connections. Against the background of these remarkable improvements, the DNS system got no better at all — anyone with a PC was still a
second-class citizen with no address, and it was Napster, ICQ, and their cousins, not the managers of the DNS system, who stepped into this breech.
These companies, realizing that interesting services could be run off of PCs if only they had real addresses, simply ignored DNS and replaced the machine-centric model with a protocol-centric one. Protocol-centric addressing creates a parallel namespace for each piece of software, and the mapping of ICQ or Napster usernames to temporary IP addresses is not handled by the net’s DNS servers but by
privately owned servers dedicated to each protocol — the ICQ server matches ICQ names to the users’ current IP address, and so on. As a side-effect of handling dynamic IP addresses, these protocols are also able to handle internet address changes in real time, while current DNS system can take several days to fully log a change.
In Napster’s case, protocol-centric addressing merely turns Napster into customized ftp for music files. The real action is in software like ICQ, which not only uses protocol-centric addressing schemes, but where the address points to a person, not a machine. When I log into ICQ, I’m me, no matter what machine I’m at, and no matter what IP address is presently assigned to that machine. This completely decouples what humans care about — can I find my friends and talk with them online — with how the machines go about it — route message A to IP address X.
This is analgous to the change in telephony brought about by mobile phones. In the same way a phone number is no longer tied to a particular location but is now mapped to the physical location of the phone’s owner, an ICQ address is mapped to me, not to a machine, no matter where I am.
This does not mean that the DNS system is going away, any more than landlines went away with the invention of mobile telephony. It does mean that DNS is no longer the only game in town. The rush is now on, with instant messaging protocols, single sign-on and wallet applications, and the explosion in peer-to-peer businesses, to create
and manage protocol-centric addresses, because these are essentially privately owned, centrally managed, instantly updated alternatives to DNS.
This also does not mean that this change is entirely to the good. While it is always refreshing to see people innovate their way around a bottleneck, sometimes bottlenecks are valuable. While ICQ and Napster came to their addressing schemes honestly, any number of people have noticed how valuable it is to own a namespace, and many business plans making the rounds are just me-too copies of Napster or
ICQ, which will make an already growing list of kinds of addresses — phone, fax, email, url, ICQ, … — explode into meaninglessness.
Protocol-centric namespaces will also force the browser into lesser
importance, as users return to the days they namaged multiple pieces
of internet software, or it will mean that addresses like
icq://12345678 or napster://green_day_fan will have to be added to the
browsers repetoire of recognized URLs. Expect the rise of
‘meta-address’ servers as well, which offer to manage a user’s
addresses for all of these competing protocols, and even to translate
from one kind of address to another. (These meta-address servers will,
of course, need their own addressses as well.)
Its not clear what is going to happen to internet addressing, but it is clear that its going to get a lot more complicated before it gets simpler. Fortunately, both the underlying IP addressing system and the design of URLs can handle this explosion of new protocols and addresses, but that familiar DNS bit in the middle (which really put the dot in dot com) will never recover the central position it has occupied in the last 2 decades, and that means that a critical piece of internet infrastructure is now up for grabs.
Thanks to Dan Gilmor of the San Jose Mercury News for pointing out to me the important relationship between peer-to-peer networking and DNS.