On Dec 25, 2009, at 7:57 AM, Anton Kapela wrote:
On Fri, Dec 25, 2009 at 5:44 AM, Vadim Antonov <avg@kotovnik.com> wrote:
The ISP industry has a long way to go until it reaches the same level of sophistication in handling problems as aviation has.
It seems that there's a logical fallacy floating around somewhere (networks have parts and are complicated, airplanes and flight involve lots of parts and are also complicated, therefore aircraft are like networks). I assert that comparing 'packet switching' to an industry that has its roots in the late 1800's and had its first "hello world" moment in 1903 isn't terribly fruitful.
As someone with a fair amount of experience with both, I have to disagree with you. Yes, there are differences, and, yes you have to keep comparisons and the like in perspective, but, there are definitely areas where networking could learn from aviation, and, to some extent, vice versa.
Further, aircraft are the asymptotic limit of 'singly homed transit.' Because of this, I think one could argue that pilots and ATC must be held to a different professional standard due to the nature of public trust at risk. At the other end of our strawman spectrum, we have end users who must accept the risk that their provider will be unable to connect them to lolcats.com on occasion, perhaps as often as 0.01% per year, and most are happy to accept this. Four nines survivability on flights, clearly, won't work.
Correct... As I stated in my earliest posts on this subject, while there is value to be obtained in looking at how aviation has improved its safety/reliability record over the years, there is also value in recognizing the cost/benefit ratio of some of those improvements. If you draw a graph with one curve arcing from bottom left towards upper right, steepening as it goes to the right, that line can be thought of as the amount of cost of achieving additional reliability. A second curve sloping from top left to bottom right, flattening out as it goes to the right can be thought of as the gains achieved from those additional 9s of reliability. Finally, the point where those two curves intersect is defined by the cost of outages and/or downtime. Interestingly, this same diagram will be familiar to most pilots, but, the two arcs will be induced drag (drag from producing lift) and parasite drag (drag from friction with the air). The point where they meet is called "L/D Max" and is the airspeed at which the given aircraft will achieve it's best glide ratio.
What I'm getting at is that after following this thread for a while, I'm not convinced any amount of process-borrowing is going to solve problems better, faster, or even avoid them in the first place. At best, our craft is 1/3rd as "old" (if that's somehow I measure of maturity) as flight and nobody is being sued to settle 200+ accidental deaths because of our mistakes.
There are lessons to be learned that are valuable. Both from things aviation has done well that we could emulate, and, from things aviation has done poorly that we should avoid. There are also additional lessons to be learned about the differences in cost/benefit analysis between the two disciplines. Owen