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Comment Re:Why do Insurance companies make it so hard then (Score 1) 99

For some sustained period of your life, your calorifie intake exceeded your energy expenditure and you put on weight. You may have reduced your calorie intake since then and stabilised your weight gain, however you have not reduced your calorie intake and/or increased your energy expenditure sufficiently to /reduce/ your weight.

At core, it is that simple.

There are details that matter though. E.g., different foods are digested and metabolised in different ways, and can produce different hormonal and neurological responses. E.g., sugar is processed quickly, alters insulin levels quickly, and your brain tends to crave it - so it doesn't fill you up. Higher fibre, less processed, and lower glycaemic index foods tend to be better for weight control. They make you feel full for longer, take more energy to digest, and your body responds more slowly. E.g., fresh fruit is great in that respect. Indeed, even *fats* aren't a bad thing per se - probably better to get your energy from fats than sugary things. Particularly, unprocessed (esp, never significantly heated) plant fats and oils from nuts, legumes, avocados, etc., seem to be good for us.

Also, not all exercise is equal either. You see people in gyms doing weights trying to lose weight - completely wrong. Sustained, aerobic exercise using the biggest muscles in your body: your legs and your stomach muscles (for breathing - not sit-ups). Doesn't have to be super-hard either, you actually burn more fat at *lower* intensity aerobic exercise. At higher intensities of aerobic exercise (i.e. the kind you can only sustain for ten or twenty minutes), your body uses sugars as they're easier to convert to energy. If you reduce the intensity a bit, down to a level you could sustain for an hour+, you should get to a zone where your body can meet the energy demands by burning fat stores - and your body usually will prefer to burn fat stores when it can (carbohydrate stores being more limited and precious).

The biggest issue is finding time for exercise. I hate the gym myself. To get exercise, I need to build it into my life so it's simply unavoidable. For me, that means relying on a bicycle to get to/from work. Cycling has worked for others. E.g., see: https://theamazing39stonecycli... - he lost 170 kilogrammes (~376 lbs) in a couple of years, by cycling.

If you review your life, make changes to how and what you eat, and exercise, it is possible to get to a healthy weight. Not easy, but you can make it happen.

Comment Re:Why do Insurance companies make it so hard then (Score 1) 99

There was an excellent programme in the UK called "Secret eaters". They would have obese people - often a set from same household - who couldn't understand why they weren't losing weight, despite eating all healthy, compile a food diary. These food diaries would nearly always show the person was eating well, and should be losing weight.

The good bit was they'd then put the person under surveillance, with cameras in the house and (unbeknownst to the people) detectives following them around. Then they would compile a list of what the people were _actually_ eating. Pretty much universally, the obese people in their programmes were self-delusional about their eating. E.g., they'd tell themselves "But I only eat a salad for lunch" while ignoring all the sugary and/or fatty snacks they were eating at their desk or on breaks before other, and/or ignoring various calorie-rich sauces or other sides they were having with the salad - that type of thing.

So, I don't believe you.

Comment Re:explain how you rewrite the laws of physics (Score 1) 130

The system is subverted, e.g. has been modified, so that when Borland Turbo is loaded into memory it too is subverted. Alternatively, DOS 22h is replaced with a version that checks every disk write to see if it is the beginning of a DOS executable, and if so, subverts it. Alternatively, ... etc.

There are surely many ways. Otherwise, you are arguing that DOS is not vulnerable to a broad range of all-powerful subversions, which is patently untrue.

Comment Re:not trusting is hard work (Score 1) 130

Not sure what car manifolds have to do with it - argumentum ad vehiculum.

Again, you're assuming that an old toolchain can only have old attacks. That's a flawed assumption. A modern attacker can subvert your system so that old toolchains are subverted to apply further subversions.

Are there practical steps we can take to raise the bar and make such attacks much harder to execute. Sure. Can we guarantee our system is free of such subversions, without either trusting others to some degree or building the system entirely ourselves: no we can't. Which was Thompson's point.

Comment Re:Borland predates Linux, ELF (Score 1) 130

I'm not familiar with DOS exe format. However, there must be some well-defined entry point.

Thompson's attack doesn't mean that any subversion of the Borland 1.0 compiler is limited to when the Borland 1.0 compiler was created. Thompson was making an extremely general point about security in programmable systems: You either build pretty much all of it yourself, or else you must invest trust in others.

Comment Re:Borland CDs are read only (Score 1) 130

Perhaps I wasn't being explicit enough.

The CDROM might be read-only, but the software has to be copied into memory by something in order to run. As per Thompson's original point, it isn't sufficient to protect one piece of the system. As he stated, his attack implies that *every* programme that is involved in the handling of software must either be validated to the same level as having written it yourself OR you must invest trust:

In demonstrating the possibility of this kind of attack, I picked on the C compiler. I could have picked on any program-handling program ..

(emphasis mine).

Indeed, his point on trust extends beyond just programme-handling programmes to all logic (soft or hard) involved in the handling and the running of software. Thompson mentions microcode almost after the text above:

As the level of program gets lower, these bugs will be harder and harder to detect. A well-installed microcode bug will be almost impossible to detect.

Since Thompson, we've had "Blue pill" rootkits that use x86 virtualisation features to effectively run themselves as microcode under the victim system (and unbeknownst to).

Comment Re:Easy enough to handle trusting trust (Score 1) 130

Why do you think a new trojan can not infect old binaries?

The Thompson attack is what we would recognise today as a class of virus. Indeed, as Thompson's point was a general one about the unavoidable need to trust others, if one did not build every component capable of basic logical manipulation oneself, to fully counter Thompson's attack you would have to be able to counter every possible kind of virus and rootkit - and not just of the software, but also of any other firmware and microcode that might handle or be involved in running your code. (Read his paper, he is clear he envisions his attack could be implemented in lots of ways and places in the abstract).

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