Paul Francis
Addressing IP Address Space
by Baaba Andam, student writer
Imagine that basic phone service only allowed you to make outgoing calls, but not to receive incoming calls, and that to receive incoming calls you had to pay a lot more. “You would not think much of that service,” says Paul Francis, “and yet that is essentially how the Internet works today.” Paul is often blamed for this. “The designers of the Internet Protocol didn’t plan for success,” Francis explains. “They made the address space too small to accommodate all the computers that would eventually attach to the Internet.”
He continues, “In the early 90s, when the research community became aware of this problem, I designed a quick-and-dirty fix called Network Address Translation (NAT) that was just meant to tide us over until the Internet could be rebuilt with a bigger address space. NAT essentially allows many computers to share the same address.” Unfortunately, NAT worked so well that the rebuild, something called IPv6, never happened, and we’ve been living with NAT ever since.
Before the IP address crunch, any computer programmer could build an application to run over the Internet, and it would just work,” says Francis. “Back in the 80s, you didn’t have to be a Yahoo or a Google and set up a bunch of servers to run a chat application. You could just write the code and it would work over the Internet.” Francis spends his time these days trying to figure out how to get the Internet back to what it used to be.
Of course it’s not as simple as it was when only academics used the Internet. These days you have to defend against everything from teenage script kiddies to the Russian mafia. “We’re looking at layering a signaling system on top of the Internet,” explains Francis. “This system would allow users to identify each other with user-friendly names, but would prevent incoming connections unless the receiver was convinced that the connection was OK. This might mean authenticating the remote user, understanding which application will be used, and so on.”
When pressed, Francis has to admit, “Yeah, it’d be pretty sweet to be the guy who solves the problem I created fifteen years ago.”