Chapter 3. 13h30 - SNAP Computing and the X Window System

SNAP Computing and the X Window System

Jim Gettys

paper: http://www.freedesktop.org/~jg/snap_and_X.pdf

personal: http://www.w3.org/People/Gettys/

This was a talk about how we used computers in the past, how we currently use them, and how we should use them in the future. It was a nice talk in the sense that every once in a while it's good to step back and look objectively at what's going on.

Jim started off by pointing out that in the good ol' days we used to have time-shared systems: there would be one system and everyone would share it with multiple terminals. The goal in those days was to put more and more users on fewer and fewer (often one) system(s).

Then the Personal Computer came along which changed our usage from sharing to a more selfish "mine" environment: one person, one mouse, one monitor, one keyboard, one CPU, one HDD, etc. Jim pointed out (very correctly!) that one of the biggest consequences of this new computing model is that everyone has had to become an admin, forcing us to spend more and more of our time not doing what we set out to do. At this point he went off on a bit of a tangent: he brought up how people for years have been sponsoring research to try to find out if Linux is cheaper than Windows (or visa versa) to deploy. He then pointed out that only roughly one-quarter (1/4) of IT budgets are spent on tangibles (or semi-tangibles) such as hardware and software. Three-quarters (3/4) of most IT budgets go towards administration costs.

A further consequence of the personal computing environment is that we change rolls all day long. At one point we might be developers (users), at another point we might need to configure our system in some way (sysadmins), then someone else might need help with their computer (either as a developer or for configuration), then a spouse might call from home because they can't seem to print anymore. Every time we change rolls we need to re-authenticate ourselves, this becomes annoying. When it comes to helping our spouse at home, it would be nice to see what they see on the screen instead of trying to talk them through something vague.

In the future Jim speculated that sharing would come back in style. It would be nice to go to a friend's house and be able to use their 63-inch plasma TV as an output device for your cell phone. Maybe there's a wireless keyboard laying around that you could use too. Better yet, you wouldn't take over the entire screen with your cell phone, but rather you'd get a window in which you could work. That way Sally could carve out another window for herself to check her email via her PDA. The short and the long of it is: all devices that we use to interact with our electronics become public property (in a controlled and coordinated way).

Wires are one-to-one connections, and inherently evil (:-)); everything should be wireless. We have an entire class of devices (USB/Ethernet hubs and switches) just to try to work around the fact that wires are one-to-one devices.

Since this was so much a "wouldn't this be nice" kind of talk Jim didn't dwell very long on any issues of how exactly this would work. He did mention that there is research currently going on involving some parts of this vision. He did also try to spend some time on pointing out just how fundamental the changes to X would need to be in order to implement these ideas. For example X would need to get away from the idea of a static configuration file. Oddly enough, he's quite certain that we're really not as far away from this vision as one might expect; in his estimation all these ideas are do-able, it's just a matter of some typing (he must be a manager :-)).

Jim did tip his hat and wave his hands a lot when talking about security. Obviously there would need to be some mechanism to ensure that I can't steal Sally's password when she logs into her email service while we're both using the same screen at the same time. Also, maybe everyone in a room is trying to watch a movie so having somebody's cell phone keep popping up as a window in the middle of the action might not be appreciated by many others. One thing he did say that was quite interesting is how all of our current security models really aren't suited to this task. Take ssh, for example, I'm not prepared to give everyone who wants to use my display device an account on my machine. To further drive home the point of how inadequate our current security mechanisms are he said that we must be able to allow people we do not trust to use our resources.

In conclusion:

• security should be a tool to enable us, not to restrict

• all occurrences of the word "one" should be banished from all computing environments.