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Comment Spam stems from lack of negative feedback (Score 5, Interesting) 114 114

Control Theory is applied mainly to electronic systems, but it's equally applicable to all systems everywhere, with no exception. That includes networking, and it even governs human systems.

It's a truism in Control Theory that a system without negative feedback is a system that is out of control. All non-trivial systems without negative feedback head towards an uncontrolled state on the slightest perturbation of initial conditions.

Email is one such system. It was designed without negative feedback back in the early days of the academic Internet before malicious actors appeared on the scene. Because there is no "cost" associated with sending an email, the system went out of control --- the primary effect of that is spam. (This "cost" has nothing to do with money.)

In Control Theory terms, "cost" is any control metric that tracks an undesired effect and reduces that effect when applied to its cause. One of the most universal undesired effects is resource consumption, and that's directly applicable to the email problem because many kinds of resources are used up by spam when it arrives at MTAs and at end-user mailboxes --- examples are CPU time, storage space, network bandwidth, end-user time, and many other things. They're all resources, and spam is the direct result of the spammer feeling no "cost" when he consumes other people's resources. There is no negative feedback being applied to his posting of spam.

"Cost" in the control theoretical sense could be many things when applied to email, for example a slowdown in the spammer's ability to post his next email proportional to the rate of sending and to the number of recipients. There are dozens of possible ways to make a spammer feel a "cost" as negative feedback for his actions, many of them leaving normal mail users entirely undisturbed by the negative feedback. Unfortunately email has none of these control methods available, and it probably never will because it's too late in the day.

One day however, a new asynchronous communication protocol will be designed to replace SMTP. It must be designed with a mechanism for negative feedback integral to the protocol and non-optional, or else the spam problem will appear again, sure as night follows day.

Note that we have many other systems out of control in computer networking, it's not just email. For example, there is no negative feedback applied to rampant abuse of user-side scripting by web pages. Web developers feel no cost regardless of how much end-user CPU, storage, or network bandwidth they employ, and since there is no negative feedback applied to their over-use, browsers typically have their CPUs pegged at 100% and the Web has turned to molasses. As techies we try to control the Web excesses with NoScript (for example) just as we try to control spam with SpamAssassin, but these are just fighting symptoms. You can't cure a disease by fighting symptoms.

This is a universal truth. No negative feedback spells trouble ahead.

Comment Mob dev is design by the least experienced (Score 1) 126 126

There's a problem with mobs: they gang up and lynch anyone who isn't part of the mob.

This doesn't happen just in westerns. It's been happening since the dawn of time, because it's a natural property of crowds: the least able thinkers are the ones most likely to be swayed by group-think. And one of the strongest group-think arguments is "Outsider, danger to group, kill it", which is a very effective survival M.O. for life below a certain threshold of intelligence. The combination of these two aspects of mob behaviour is predictable.

That makes TFS and TFA a bit of an exercise in wishful thinking. Development by mobs could (in theory) work well, but only in the very unlikely situation that the mob has a statistically improbable makeup in which independent thinkers are dominant and are also well informed and technically experienced. Unfortunately that scenario lies in "pigs will fly" and "hell freezes over" territory.

The perfect number in team programming is two people of similar experience, because then they can't gang up and form a lynch party. If they don't immediately agree then it creates a stalemate which can be broken only by rational explanation / defence or by terminating the pairing. It's an ideal situation, yet not too hard to arrange.

Mobs don't really have a place in intellectual endeavours, and programming is one of those.

Comment You will not be able to reach device endpoints (Score 1) 595 595

What will is miss?

On IPv4, you won't be able to reach the endpoints of millions of computers and other devices that have IPv6 addresses now (eg. Android always looks for IPv6 connectivity on startup). This is relevant not only in the east where new IPv4 address blocks are no longer available, but also here in the west where IPv6 deployment is continuing and accelerating.

Your "What will I miss?" question is pure IPv4 thinking, because in IPv4, NAT makes almost everything except static public servers inaccessible as individual device endpoints are typically hidden. That's a severe limitation in IPv4, and you've become conditioned by it and so you're expecting a reply involving a list of websites. It's incredibly narrow thinking.

With IPv6, a user on any random portable device can share an object with you directly, not needing to upload it to a public website first. You could be chatting with them on IRC and they write "Hey look at this wierd stuff I'm seeing on my phone", and you just point a browser or image app at their IPv6 address and bingo, you see whatever they're making available, live. You can't do that with IPv4 because there aren't enough IPv4 addresses available for every device to have one, and connections to arbitrary endpoints are typically blocked by NAT anyway.

That's why in IPv4 people have to upload stuff they want to share to public websites first, which is annoying and limits the content protocols that can be used. Applications can be much more versatile and immediate in IPv6, and you will be missing all that directly-available content if you can't reach the IPv6 endpoints of devices. It can't be done on IPv4.

Comment List of benefits of IPv6 for dumb END USERS (Score 1) 595 595

What are the beneficial FEATURES to dumb end users?

I'll bite, as that's a perfectly reasonable question. OK, no technical info at all in the following list, the technical answers are given in detail elsewhere.

Benefits of IPv6 for dumb (meaning non-technical) END USERS:

- All protocols work over IPv6, unlike the breakage on IPv4.
- IPv6 "just works" without user setup, great autoconfiguration.
- As many public IP addresses as you want for devices on IPv6.
- Safer because network security is built into IPv6, not optional.
- Add IPv6 to see the whole Internet, not just the IPv4 part.
- New quality of service features for stutter-free video or gaming.
- Faster networking for a better all-round user experience.

Each of these 7 benefits has a technical reason for which the corresponding improvements were added to IPv6 by design to improve on IPv4. These benefits are available to everyone, and non-technical users don't need to understand the details to enjoy the benefits.

Comment IPv6 has been working fine, no issues (Score 4, Insightful) 595 595

The official "switch-on for good" of IPv6 a year ago was entirely seemless in my experience. There wasn't anything to fix, as nothing was broken, and IPv6 autoconfiguration handles everything so there isn't even any setup involved, it just works. This simplicity will be a boon for non-technical users once the IPv6 rollouts gain steam.

Unfortunately the ISPs are still dragging their feet and so public rollout is slow, but it's an always upward trend, and the adoption curve is close to exponential so IPv6 will be ubiquitous before long. So many ISPs are currently planning their rollouts that there's going to be a sudden upsurge when they finally appear.

People shouldn't talk about switchover to IPv6 though, that's not how it works. IPv4 and IPv6 networks run together side by side, and you use both together. Your application (eg. browser) generally picks IPv6 if your destination is accessible on that network, or else it falls back to IPv4. This is all automatic of course. It's better described as a switch on of IPv6 by your ISP followed by your gradual increasing use, not a switchover. There is no plan to switch off IPv4. The last remnants of IPv4-only equipment could still be around and operational for decades ahead.

IPv6 works so well that I recommend everyone to get on it as soon as they can. You'll be able to see 100% of the Internet, whereas if you don't have IPv6 then you're only seeing a part of it. IPv4 is by far the larger part for now of course, but it's not all of it, and the parts you can't reach are growing daily.

Happy First Anniversary of the official turn-on, IPv6! :-)

Comment Cass "Cognitive Infiltration" Sunstein (Score 1) 121 121

This is the same man who proposed infiltrating and attacking any groups that dared think something of which his government didn't approve.

Although as a deeply-connected member of the Obama Administration, I'd have to agree that, at least when it comes to his own efforts at governance, "Human beings often see coherence and planned design when neither exists."

Anyone who's ever worked for George understands George himself was, however unconsciously, the model for both Darth Vader and the Emperor. Frightening but revealing that Sunstein would use this - a ruthless dictator who in truth has neither coherence nor a plan - as his template for constitutional government.

Submission + - FEMA Will Require States to Examine Climate Risks in Disaster Planning->

mdsolar writes: The Federal Emergency Management Agency announced yesterday afternoon a change in its requirements for State Hazard Mitigation Plans that NRDC has been advocating for nearly three years. These plans, which states develop in order to prepare for future natural disasters, must now consider the projected effects of climate change on hazard risks.

Back in 2012, NRDC petitioned the agency to adopt this requirement because most states' plans did not account for climate change when assessing their future vulnerability to natural hazards. Yet as FEMA recognized yesterday, "the challenges posed by climate change, such as more intense storms, frequent heavy precipitation, heat waves, drought, extreme flooding, and higher sea levels, could significantly alter the types and magnitudes of hazards impacting states in the future." It's critical that states begin to plan ahead for these changes and develop strategies to reduce the risk of harm to people and infrastructure.

Over a year ago, FEMA told us that it would be revising its guidance for State Hazard Mitigation Plans to require consideration of climate change, as we had asked. President Obama officially confirmed the change last summer, and in the fall FEMA published a document summarizing the revisions....

The new guidance is clear that in order for a state's plan to be approved by FEMA, thereby making the state eligible to receive federal funding for pre-disaster mitigation projects designed to build resilience, it must "include considerations of changing future conditions, including the effects of long-term changes in weather patterns and climate on the identified hazards...."

The new requirements will apply to plans that are submitted in March 2016 and beyond. This phase-in period allows states some time to begin integrating climate change information into their plans, if they haven't done so already.

Link to Original Source

Submission + - The melting of Antarctica was already really bad. It just got worse.->

mdsolar writes: A hundred years from now, humans may remember 2014 as the year that we first learned that we may have irreversibly destabilized the great ice sheet of West Antarctica, and thus set in motion more than 10 feet of sea level rise.

Meanwhile, 2015 could be the year of the double whammy — when we learned the same about one gigantic glacier of East Antarctica, which could set in motion roughly the same amount all over again. Northern Hemisphere residents and Americans in particular should take note — when the bottom of the world loses vast amounts of ice, those of us living closer to its top get more sea level rise than the rest of the planet, thanks to the law of gravity.

The findings about East Antarctica emerge from a new paper just out in Nature Geoscience by an international team of scientists representing the United States, Britain, France and Australia. They flew a number of research flights over the Totten Glacier of East Antarctica — the fastest-thinning sector of the world’s largest ice sheet — and took a variety of measurements to try to figure out the reasons behind its retreat. And the news wasn’t good: It appears that Totten, too, is losing ice because warm ocean water is getting underneath it....

That’s alarming, because the glacier holds back a much more vast catchment of ice that, were its vulnerable parts to flow into the ocean, could produce a sea level rise of more than 11 feet — which is comparable to the impact from a loss of the West Antarctica ice sheet. And that’s “a conservative lower limit,” says lead study author Jamin Greenbaum, a PhD candidate at the University of Texas at Austin.

Link to Original Source

Submission + - Guardian petition for fossil fuel divestment receives 60,000 signatures->

mdsolar writes: In less than 24 hours, more than 60,000 readers have joined a campaign on the Guardian’s website asking the world’s largest charitable foundations – the Bill and Melinda Gates Foundation and the Wellcome Trust – to divest their endowments from fossil fuels.

It was, in the words of one reader, “a big day in civic journalism”. The Guardian’s website and front page have never looked quite like it, as oil dripped down where the news would normally be.

Link to Original Source

Submission + - Japan utilities set to scrap five aging nuclear reactors->

mdsolar writes: Three aging nuclear reactors in Japan will be decommissioned due to the high cost of upgrading them in line with tougher safety standards set after the Fukushima disaster, their operators said on Tuesday.

Another two reactors were also likely to be scrapped, local media reports said, with announcements expected later in the week.

The moves are the first concrete sign that Japan's nuclear industry is heeding a government request to shut down older reactors that are considered more vulnerable to natural disasters in the hope that it will ease public concerns about a restart of other reactors.

All 48 of Japan's nuclear reactors were taken offline after an earthquake and tsunami set off meltdowns at Tokyo Electric Power's Fukushima Daiichi plant in 2011.

As many as two-thirds of the country's reactors may never return to operation because of high costs, local opposition or seismic risks, a Reuters analysis showed last year.

Link to Original Source

Comment Re:Coal use predicted to peak soon (Score 1) 190 190

So, predictions for 5 years for the world and 25 years for one country. Where is the 30 year prediction? China is committed to peaking emissions by 2030 which is only 15 years off. Apparently, the first report you cited missed this and some other things as well.

Real programmers don't bring brown-bag lunches. If the vending machine doesn't sell it, they don't eat it. Vending machines don't sell quiche.