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Comment The dam is valuable, the parking lot crack not muc (Score 2) 206

> Your thought process is akin to saying it makes no sense to spend $5k to patch a 2" crack in a dam because the crack is only 2".

No, the dam is extremely high value, therefore you pay attention to it. When the Banqiao hydroelectric dam failed, it killed hundreds of thousands of people. So the dam is at the top of your "most protected" list. What I'm saying is this:
There's a 2 inch crack in the dam, and a 2 inch crack in the parking lot. What's your first step? Your second step?

Obviously your first step is "fix the crack in the *dam*". The correct second step is less obvious - look for more cracks in the dam. You shouldn't worry about the 2" parking lot crack until you've double checked everything about the dam. Again, see Banqiao.

Comment Doesn't hurt, besides performance and trust (Score 1) 206

You certainly can do both. There will be a performance hit, small or large depending on cipher mode. You should double-test your backups in case either layer of encryption fails. I would recommend using a fast mode for the full-disk, keeping in mind it won't be NSA secure. So thinking about privacy, you'd pretend the full-disk isn't there - it's just a backup just in case.

Comment One of us is misunderstanding the other (Score 2) 206

FYI I've been a fulltime security professional for 20 years. My advice is based on what I actually do when your bank hires me to test their security, how I can actually hack your accounts.

> No, the problem is, you try to seperate, what seems important and confidential to you. And there is the mistake.
> Because it requires you to think about what's confidential all the time. ...

> reading some private e-mails won't hurt now, because if they are left in the cache in your firefox profile

I never said "encrypt one file at a time". I said encrypt YOUR files separate from your (soon to be ex-) wife's files. That includes /home/allo/.cache/mozilla/firefox/

Obviously you might *also* separately encrypt your most important files, such as a password manager datastore, a second time. But no you don't have to think about what to encrypt, all of your personal files are encrypted, including your browser cache.

> Why would you encrypt /home and not /? Is there any reason preventing / encryption? No. ...
> So you install your system, make a checkmark at "full encryption"

That SEEMS like a good idea, if your understanding of encryption is checking a box. As one of the guys who implements what happens when you check that box, I think maybe we should remove that checkbox so it doesn't mislead you. It LOOKS like it makes your system secure, right? Unfortunately, it mostly just makes your system slower. I can still see your ECB penguin. :)

There are both practical and technical problems with full-disk as opposed to per-user. The biggest practical problem is easily summarized as:
Do you want your files to be accessible to your soon to be ex- wife?
Generally, no, users should not have access to another user's files. When your visiting step-brother asks to borrow your laptop, he should not be handed an unencrypted copy of all of your personal and business files.

There is also a fundamental technical problem with full-disk encryption such that full-disk can either either be weak, or ridiculously slow, in most cases. It has to do with what are called "cipher modes". ECB is reasonably fast, but provides little security. CBC is secure, but modifying one sector requires updating every sector on the disk which follows it (meaning it takes a few minutes to save 1KB). Other modes are in between the two. We think that we *might* have that problem beat with a new approach, but I don't trust it yet.

> If you need to decide what ends up in your backup, you may forget something important. If you backup everything, you will have everything and cannot forget something important. The same applies for encryption.

That's absolutely true for backup, definitely. The only backup systems I recommend backup the whole damn machine. The system I designed makes *bootable* backups, that can be booted in-place as virtual machines. For encrypting and otherwise securing confidential data, there's a fundamental conflict between availability vs confidentiality and integrity. You may want to make your mp3 files openly available on your network, so you can play them with any device in the building. You might even store them in the cloud, easily accessible over the internet. You should NOT make your most confidential data readily accessible to every device on your network, including your IP camera and other cheap IoT devices with a thousand vulnerabilities each. If you're serious about security, you DO need to think about which items should be easily accessible to everyone in the company/house and which should be locked down tight.

I'll give you an extreme example of identifying the most confidential data and a very common example of failing to do so. The Coca-Cola company has perhaps a million documents that shouldn't be published on their web site, documents for employees only. Only their 146,000 employees have access to those documents, because they have some protection. (And probably anyone who cares to look can findleaked copies online). Coca-Cola also has the secret recipe for Coke. The secret recipe can't be found on Google only because Coca-Cola properly identified their most critical assets and protects them accordingly. The secret recipe isn't protected in the same way that the campus wifi password is protected. Coca-Cola has done it right.

On the other hand, it's common for web forums and similar software to treat each user's user name and password as confidential information. The security of these forums assumes that a bad guy doesn't know the target's username or password. They then expose the username via a search function or something similar. So it's a "secret" in that you assume that bad guy doesn't know it, but then it's not so secret when you display it on their list of posts. I pointed this out to the developers of two such systems and they didn't quite "get it". One understood a couple years laterb when there was a rash of attacks exploiting this problem. The second understood when I demonstrated that I could log in as admin. It *is* important to be clear on which data is public, which is "not shared", and which is secret.


Comment Security 102, chapter 1 - Risk Analysis (Score 4, Insightful) 206

If you go a bit beyond the corporate-mandated annual security training, most information security curriculum says that step one is identifying the assets at risk and their value. It would be silly to spend $50,000 turning your garage into a vault to protect a $15,000 car, and similarly for information security the value of the asset determines the maximum effort you should put into protecting it. This not only avoids wasting more time/money/hassle than the asset is worth, but it allows you to spend your efforts on the most valuable assets. Any time/money spent on a low-value asset is time NOT spent protecting a higher-value asset.

The identity of your favorite gaming site is worth about 5 cents US, so it is error to spend more than 5 cents worth of time trying to protect that information.

Additionally, in most cases it is better to protect and encrypt data on a per-account basis, for both technical and practical reasons. On a laptop, that means you encrypt the home directory, not the system. Multiple user logins have separate encryption, and one account can't access the encrypted files of another account. If you want to take it a step further, you can have a work account on the machine and a separate account for checking personal email, etc. Along with the obvious security benefits, that avoids having the browser or search engine auto-complete a URL based on *personal* browsing history in the middle of a presentation.

Given per-account security, a guest account with restrictions on it is quite feasible, and a theif would likely click the guest account.

Comment Per-account encryption is often better than full-d (Score 1) 206

In many cases, it is better to encrypt files for each account separately, rather than full-disk encryption. This is partly because most full-disk encryption sucks in one of two ways. (Google "ecb penguin" for an example.)

Along with avoiding technical problems with full-disk encryption modes, this improves security because the user of one account can't access files owned (and encrypted) by another account. You can even have a "guest" account for a houseguest to use, and guest can't access your files.

Since you have a guest account anyway, the guest account might also be configured appropriately given the knowledge that a thief might one day use it.

Comment Self-taught is great. The language is the glossary (Score 4, Interesting) 137

> I taught myself PHP

That's awesome. I respect anyone who has the desire to learn, the puts in the work, and has the discipline to see it through.

PHP is of course a language, a set of vocabulary. At the back of any textbook, you'll find a glossary, the language or vocabulary used in the book. You've already learned the language, the glossary, of PHP programming. If you look, you may find there's a lot of cool stuff in the other parts of the book, systems architecture stuff, software engineering, analysis of algorithms, etc.

You need to learn a programming language or two before you learn analysis of algorithms or software engineering, because the languages are the vocabulary words of the field.

To give a concrete example, when I started my current job, the company had a software system that worked - mostly. A team programmers had worked several years on it, and all knew the language they were working in. Customers just wanted it to be faster. It was definitely too slow. Although it was my first month on the job, when I heard the complaints of slowness I said in a meeting "I'd like to take a look at that; I can probably make it 20%-30% faster easily enough for now, then do more after I understand how it all works." The team was rather skeptical, in fact they chuckled out loud at my claim, saying "I rather doubt you can do that". "How long do you think that'll take?", they asked. "Give me a week", I said, though I hadn't yet seen the code. They laughed again, hundreds of thousands of lines of code and this new guy was going to make it 20%-40% faster in a WEEK? Doubtful, they said. To put me in my place, they said "sure, go ahead and try that [wiseguy]."

As I left the meeting I realized I had just taken a big risk. When I went home I told my wife that I had just bet my reputation at the new job on a claim I only hoped I could fulfill. If I failed, it would establish that I'm an arrogant prick. If I succeeded, I'd be known as possibly the best programmer in the building.

Well a week later I had it running 30% faster. Why could I, in a week, make drastic improvements to code they'd been trying to speed up for months and years, code I'd never even seen before? They all knew the language almost as good as I did. But I had been taught to study much more than the language. They knew C, Perl, and Erlang; I knew algorithms and cache theory. So in a week I did in fact make major improvements to their years of work.

Now, I'm going to go upstairs and check the progress of my benchmark. Now six months into the job, a major customer again complained about slowness, so I've been looking at that for a few days. I hope to see that my three day's work has made the system another 20% faster. I'm a tad nervous because I need to impress the new boss, I think that by learning more than just the language (glossary terms) I'll be able to do that.

Comment Can still ask permission, or fair use (Score 1) 141

It is perhaps worth noting that the guidelines are an additional grant of license by Paramount / CBS. People who want to do something outside of those guidelines can still ask permission, and I suspect it would be granted if it were in the same spirit as what the guidelines envision.

Of course, people can also still make Fair Use works, and "not for profit" gets you halfway to fair use.

> Star Trek Continues also violates the guidelines, but I have a hard time seeing how their copyright infringement is harmful to CBS/Paramount in any significant way.

It appears CBS and Paramount may agree with you - they haven't taken any enforcement action against Star Trek Continues, as far as I know.

I don't think CBS and Paramount could announce a policy of allowing "non-profit" use with professional cast and crew. They can be forced to honor whatever policy they publish, and a producer could pay himself a salary of $1 million. No "profit", that's his salary as professional producer.

Comment They compete in many projects, share community (Score 1) 96

The hardware is vastly different between the Arduino and the Pi, but in neither instance is the hardware the point. The point is all the community and everything which makes them easy to use, even for hobbyists.

At work we had a "show and tell" type event for a while. One guy brought his RPi, which he had hooked up to some triacs (think relays) to allow it to turn 120V devices on and off. I shared that I had built almost exactly the same thing with an Arduino. (I had also done the same with an old Pentium I got from the scrap pile). So same project, he used an RPi, I used an Arduino.

I'm not the only person who owns both RPi and Arduino - they attract some of the same buyers and community members. Sometimes when thinking about a project, I'm not sure at first if I want to do it with the Arduino or with the Pi. The Arduino probably *could* handle it, but there wouldn't be room left to add features later. So this Arduino I have right here and this Pi I have in this red case directly compete for my projects, even though the hardware is vastly different.

Comment What possesses a man to destroy investor's furnitu (Score 1) 62

> after it made a hole in his desk
> Still, what possesses a man to say "This thing cannot possibly work" after having seen it work?

The same thing that possesses a man to destroy his potential investor's furniture? ;) LOL

Seriously, I can only imagine your face when he said that.

Comment John Elway on Trevor Siemian (Score 1) 290

That reminds me of John Elway on Trevor Siemian. Siemian was the last quarterback drafted that year. He had already lined up a job in real estate because he figured he might not be drafted - he wasn't that good. Fans were surprised and a bit dismayed when Elway drafted him for the Broncos, who were a powerful team -they won the Superbowl that year. Elway said Siemian "has potential".

It turns out that in his first year as a starter Siemian had a an 18-10 touchdown-to-interception ratio and an 84.6 passer rating, both stats better than Peyton Manning and Brock Osweiler in the previous Superbowl-winning season.

Elway later reminded one fan who had been dismayed by the Siemian pick that Elway does indeed know how to spot potential:

Comment Publicana (Score 1) 74

The Roman Republic issued government contracts to build aquaducts, chariots to publicani (publicly held corporations) who bid on the projects. One publicana had a contract to handle the geese on the capital. Roman publicani could have numerous investors (stockholders), and be run by a few managers. Some employed thousands of workers and had limited liability.

Did the Roman corporations attract a lot of investors, like today' stock market does? Polybius wrote:
There is scarcely a soul, one might say, who does not have some interest in these contracts and the profits which are derived from them.
Polybius, Histories IV, circa 170 BC

Somebody lied to you, Silentcoder. A lie big enough that one must rewrite thousands of years of history to believe it.

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