Mobility is the area we have done the least work on. If you want everyone to be able to move about and update their Palm without interruption, the Internet makes that very hard to do today.
What do you recommend?
We're trying to figure out where to start.
What can be done to boost Internet performance?
Routers at the core of the Internet process every packet, yet are connected in topology to only two or three neighbors. They process every packet to determine if it goes east, west, north or south. That's an awful lot of processing to make a simple decision. If instead of processing every packet you route in a more aggregated way it will allow us to take advantage of optical switches. A whole load of little routers, called boundary routers, sit near the big routers. They're the ones aggregating all the traffic coming up from the users. They already know where they want these packets to go. So instead you could put a simple, small, almost passive optical switch that would sit in place of that big router. And the edge routers could set up an [optical] circuit across the Internet to another edge router to which they have a lot of traffic to send.
What about the core of the Internet?
We're literally just starting on thinking about that now. In the public Internet you have people and you don't know reliably who they are. Should we make it so you do know who they are? Or should we force them to reveal who they are when it matters? I don't think there's any reason to suspect that you would have the same solution for the public versus the private. And if you believe there's only two options - public and private - maybe that's not such a bad option.
We're in the midst of a very rapid growth of the Internet caused by massive amounts of video coming onto the network. Imagine if everyone in the U.S. was watching four hours of television per day and all of that four hours of television was being delivered as HDTV over the network. The amount of capacity you'd need would be many orders of magnitude bigger than the Internet is today. That is where we are headed.
The question is could you just scale up the network the way it is today? Technically, probably. It would mean the Internet exchanges would need 10 to 20 times as much space, the routers are going to have to have 10 to 20 times the capacity, which means much more power, and it's very difficult to see how all that technology could scale in a way that you could say, yes, that actually makes sense.
It all starts to look suspiciously fragile -- no fragile's not the right word. It just doesn't seem very realistic that you could get there that way.
So what would you do?
If you ask the router companies what is their biggest problem right now their answer is power. That's their biggest constraint right now. Optical switches consume comparatively no power and they scale to unbelievable numbers. Electronics in routers are stuck with Moore's Law at best. [With routing decision pushed the edge] the core of the network lends itself very nicely to fast dynamic optical circuit switching where the circuits come and go fairly quickly, perhaps every few minutes or so. They'd be established and taken down between the routers in a way that allows aggregating all of this traffic. This I believe will lead to a much more easily scaled core of the network, for these exchange points, and a lot of this. This will enable the network to scale much faster in the way that is needed.