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If a Network Is Broken, Break It More
New submitter Aras Esor writes "When a network is broken — an electrical grid, the World Wide Web, your neurological system — one math model created by a PhD student at Northwestern University suggests that the best way to fix it may be to break it a little more. 'Take the web of interactions within a cell. If you knock out an important gene, you will significantly damage the cell's growth rate. However, it is possible to repair this damage not by replacing the lost gene, which is a very challenging task, but by removing additional genes. The key lies in finding the specific changes that would bring a network from the undesirable state A to the preferred state B. Cornelius's mathematical model (abstract) provides a general method to pinpoint those changes in any network, from the metabolism of a single cell to an entire food web.'"
... network break YOU!!!
This sig is not paradoxical or ironic.
If it ain't broke, don't fix it.
If it IS broke.... don't fix it.
The plate is chipped. She resents me gluing it back together. So she breaks it real good so I gotta go out and buy an entire new set.
my company's IT department has figured this out a long time ago
Reminds me of software bugs which are "fixed" by disabling subsystems around them. Example: in a media player, AAC playback sometimes freezes and causes glitches. Solution: disable AAC playback, ensuring that the media player does not reach this undefined and broken state.
This sig does not contain any SCO code.
The first link is a "journalistic rendering", too scarce in details. The second link is the abstract.
Let's hope the arxiv preprint will be good enough.
Questions raise, answers kill. Raise questions to stay alive.
(Are those genes selfish? Because if so, this) may be a classic case of resolving a Braess's paradox by removing a trigger for selfish behaviour.
It has to do with non-linear systems that have many points of equilibrium (Braess's paradox involves another example of the same, except the equilibrium is considered in the Nash sense).
A quotation from the arxiv paper that says what's all about:
For example, a damaged power grid undergoing a large blackout may still have other stable states in which no blackout would occur, but the perturbed system may not be able to reach those states spontaneously. We suggest that many large-scale failures are determined by the convergence of the network to a “bad” state rather than by the unavailability of “good” states.
Questions raise, answers kill. Raise questions to stay alive.
So if I have one broken leg, the best solution is to break another leg and maybe an arm?
Mechanical and electrical problems are radically different to biological ones as they dont self heal/mutate.
With a cell, you're attempting to force it into a reaction by breaking it more. We do this because we dont have the knowledge or experience to fix it ourselves. With networks it's the opposite, isolate the damage, route around it if need be and then fix the broken components. Yes that's a simple view, but the basis for fixing network issues.
If my route to Sydney is down, deliberately breaking my route to Melbourne wont help if there is a physical cable problem or some idiot down in the NOC changed the route cost to 10000 on the router. Nope, instead of one route to Australia down, I now have two.
Calling someone a "hater" only means you can not rationally rebut their argument.
An explanation of why they followed XP with Vista
So if one considers the weight distribution the bulkheads in the ill-fated Titanic as a "network" perhaps it would have been possible to save her (or at least keep her afloat long enough for the Carpathia to rescue all the passengers) by further "damaging" it.
While it has been often said that she could withstand any two bulkheads being flooded, in truth she could take many more, various simulations show that she could take at least four being flooded, in various combinations. And this was with them being COMPLETELY flooded (up to the top of the bulkhead partitions); if she were on a more even keel they would only flood to the water level.
The problem of course is that the Titanic was NOT on an even keel. When the compartments, all in the front, were flooded that caused her to pitch down. The water kept rising until it went OVER the bulkhead partition, flooding the next. This caused the weight in the front to increase even more which caused her to pitch even further and ... you get the picture.
So, thinking of this like a damaged "network"; perhaps if the captain had flooded one of the far aft bulkheads (breaking the network more), the Titanic would not have pitched downward as much and the water wouldn't have overflowed the bulkheads (they were not watertight, water could go over the partitions). This might have prevented the cascading effect which led to the sinking of the world's largest ship just two and a half hours later.
Would she still have sunk if they flooded one of the aft compartments? Maybe but it might have happened much more slowly and gently (no scenes of people falling down a nearly vertical ship!). And if the downward pitch was reduced so much that the water didn't surmount the bulkheads (the partitions separating them were quite high, much higher than the normal water level), maybe she would have remained afloat!
The builder (designer?) of the boat was on her when she sank, I wonder if he considered this? Or did the thought of damaging the boat further never cross his mind?
Send your backups offsite.
TFS and to a degree, TFA missed it. They don't claim that they have suddenly discovered this property, they claim new analysis tools that help to determine what to break and where to break it to return a non-linear network to some reasonable stable state.
For example, if the power grid suffers a de-stabilizing loss, what needs to be done to move it to a stable state rather than allowing it to go into a cascade failure. We have some tools for that already, and in fact, power is re-routed and load is dropped all the time in order to stabilize things. Better tools suggest either getting to the answer faster, finding the least damaging way to reach stability (the least customers dropped) or better certainty that the actions taken will prevent dropping the whole grid.
Nobody is claiming it's OK to leave it in that state. In fact, the same analysis tools might help to make sure that the repairs don't inadvertantly destabilize the grid again as parts go back on-line.