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Comment Re:Converted old cell phone to uplink transmitter (Score 3, Insightful) 210

Many moons ago, I got tired of what was on the radio, and I built a pirate FM station. It had a studio supplied with over 50 volunteer DJs, but most of all it had the transmitter up in the mountains, with a UHF uplink system, to allow for very broad coverage of our city. I made the uplink transmitter form a 1985 Motorola cell phone, the old brick type. It was suitably modified to put out wideband FM audio. You might be able to read about it by Googling "Radio Limbo Tucson".

You're my hero.

Comment Passwords are not the only way to authenticate (Score 2) 77

Both of you are wrong and so is Dustin Kirkland (whoever he is). The core of your error is in this statement:

Only secrets can be used as token for authentication.

That sentence is true, as stated, but only because it includes the word "token". Yes if you're using secret tokens for authentication, then the tokens must be secret. But exchanging secrets (or proof of possession of secrets, which is what most cryptographic authentication protocols do) is not the only way to do authentication. Not by a long shot. In fact, humans hardly ever use secrets for authentication.

How do you identify and authenticate your mom? Do you ask her for a secret password? Of course not. You use the same tools for both identifying and authenticating her, and those tools are a set of biometric markers. The same set of tools are also used in high security situations. Back when I was a security guard in the Air Force, I was trained that personal recognition is the very best form of authentication. Not only is it not necessary to check the badge of an individual you know personally, badge-checking is inferior to personal recognition for authentication (note that badge-checking may still be important for authorization, verifying that the person who has been identified and authenticated actually has permission to enter. Thus I was trained to always check the access control list before allowing someone near nuclear weapons).

With respect to user authentication in electronic contexts we generally use secrets because computers don't (or at least haven't) had the ability to use the sorts of biometric authentication that humans use quite effectively. But, when we equip them with biometric sensors, they can.

HOWEVER, this does not mean that biometrics are useful for authentication in all circumstances.

Secret-based authentication has the advantage that -- assuming the secret has sufficient entropy and can be assumed not to have leaked nor been intercepted and cannot be rerouted (note that that's a pretty long list of criteria, some of which are hard to establish) -- you don't have to worry about the possibility that the authentication could be spoofed. An attacker who doesn't know the secret can't fake knowing the secret.

Biometrics, though, are not secrets. They are public knowledge. This means that an attacker must be expected to have access to copies of our fingerprints or faces. The biometric authentication process is different, though. It does not rely on secrecy of the authenticator, but instead on non-replayability. If we can be certain that (for example) the fingerprint placed on the scanner belongs to the person we wish to authenticate, and that the stored template we match against belongs to the person we wish to authenticate, then we can perform a good authentication. The fact that the fingerprint is not secret does not matter.

Where biometrics fail is if (a) we can't be certain that the livescan data acquired from the sensor belongs to the person trying to authenticate or (b) the stored template belongs to the person we wish to authenticate. Part (a) is particularly difficult to validate in many contexts because faking the input isn't necessarily hard to do, and in some cases an attacker can even bypass the sensor entirely and simply inject a digital copy.

This doesn't mean biometrics are worthless, it just means they're only useful in certain contexts. And, again, their utility for authentication has nothing to do with their secrecy. And rotation is likewise irrelevant and silly to discuss. You need to rotate secrets because you can't be certain they have stayed secret and because if they have low-ish entropy they may have been brute forced. None of that applies to biometrics because they're not secrets and their utility as authenticators does not depend on secrecy.

Can we please kill this incorrect meme about biometrics as identifiers, not authenticators? They can be either, or both, and are used as both, by billions of people, every day, with high effectiveness and reliability. Whether or not they provide security depends on the context.

With respect to credit card payments, fingerprint and facial recognition biometrics are pretty reasonable tools. This is especially true if the sensors are provided by the retailer, and the consumer is providing a traditional electronic authentication (cryptographic challenge-response) with their smartphone or smart card. It's not quite as good if the smartphone is also providing the fingerprint scanner and camera, because in the event of an attempted fraudulent transaction that means the attacker is in control of those components.

But you also have to consider the model that is being replaced. Is fingerprint plus face recognition better than a signature which is theoretically matched by a non-expert human, but in practice never checked at all? Absolutely. Is it better than a four-digit PIN? That's debatable, but it's at least in the same ballpark.

Comment Re:Indeed (Score -1, Troll) 385

You're talking to grown adults.

Like hell. I'm talking to KiA and if there are any "grown adults" there, you're going to have to prove it.

We are the same free minded geeks who have been around since Internet day 1

No, you're not. You weren't born on the Internet's "day one". I was there on the other hand, and the people I knew back then would have had pieces of Gamergaters/MRAs/KiAs/and /pol in their crap. You guys aren't fit to name the people who were there at the Internet's day one.

It's getting tiresome to have the open, free, principled sites and communications networks we built being labeled as "septic tanks" by the likes of yourself

Then keep them from becoming septic tanks. As I said, "learn how to behave".

There are 2 billion people online, we built this network for them

You didn't build shit.

You people are the creationists of the internet, and you are not taking us back to the stone age.

You've got a fair amount of evolving to do before you make it to the Stone Age.

Comment Re:Most of their apps are annoying anyway (Score 1) 110

I tried Inbox, but wasn't impressed. It strips so much of gmail away that it is basically "Gmail for beginners". You want filters, labels, etc, then it is worthless.

Actually, Inbox is Gmail for power users, for people who have massive volumes of e-mail to manage. It takes a little bit of work to figure it out and set it up, but once you have, it's awesome. There are some features it lacks, like complex filters (simple filters are very easy to set up; you just move a message to a label and Inbox asks if you want to always do that. Click "yes" and you have a new filter rule), vacation auto-responder and the like, but you can always use the Gmail UI when you need to set stuff like that up.

The Inbox features that that make it great for heavy e-mail users are:

Snooze.

Many people use their e-mail inbox at least partially as a task list, especially their work e-mail. This results in having to keep e-mails that for you can't work on yet sitting in your inbox, cluttering it up and making it harder to process new e-mail. When you snooze an e-mail, it goes away until some point in the future. You can pick a date and time, or even a location (requires using the Inbox app on your mobile device). Heavy application of snooze with well-chosen times/locations lets you clear all of the stuff you can't do yet out of the way, knowing it will come back later when you can handle it.

Bundles.

Bundles are just Gmail labels, but with an additional setting that tells Inbox to group them in the inbox. This is fantastic for high-volume mailing lists. With Gmail you can get almost the same effect by setting a filter to apply a label and skip the inbox, but then you have to remember to actually go look at the label from time to time. With bundles, you get the same grouping effect but the bundles show up in your inbox so you don't forget to go look. The reason that grouping (by whichever mechanism) is useful is because when you have large volumes of email, most of which you don't actually need to read, it's much faster to scan through a list of subject lines and evaluate what's important and what isn't when you already know the context.

My process for plowing through a busy mailing list is to scan the subject lines and click/tap the "pin" icon on the few that are interesting, then "sweep" the rest. A single click or gesture archives all unpinned items in a bundle. Then I handle (or snooze until I can handle) the pinned items.

I also have a bundle (label) called "Me" that is applied by a filter that looks for my name or username in the To line or the body of the message. This helps me to be sure that I notice e-mails where people are mentioning me or asking me questions. It's the first bundle I look for every time I check my e-mail. Similarly, I have a bundle that extracts e-mails that reference my project's name. That's the second bundle I look at. Other high priority bundles are e-mails from the code review system and e-mails from the bug tracker.

Obviously there are many e-mails that mention both my project and me. That's fine; bundles are labels not folders, and it's perfectly reasonable for an e-mail to be in more than one of them. When I archive a message in one bundle, it disappears from the others. So, often I'll look at Inbox and see the "Me", project, code review and bug tracker bundles displayed, but by the time I've processed everything in the "Me" bundle, the other three have disappeared.

Delayed Bundles.

I think this vies with snooze as the killer feature of Inbox. By default, a bundle appears in the inbox whenever you receive new mail with that label. But there's lots of stuff, at least in my inbox, that I don't need to see immediately. Having low-priority stuff displayed instantly distracts me from my work, or obscures truly urgent e-mail. Also, it's more efficient to handle low-priority e-mail in bulk. So, you can specify that a bundle should only appear once per day, or once per week. Inbox will accumulate e-mail in delayed bundles and only show the bundle at the specified time.

When I start work in the morning I have a dozen or so bundles containing low-priority e-mail. I can quickly scan each of them, pinning the items I care about and sweeping the rest. I have a few bundles for purely informational mailing lists which are set to display once per week, so I only see them on Monday morning.

I'd like a little more granularity on this feature. Specifically, I'd really like to be able to set some bundles to show, say, every three hours. Then I'd only allow the highest-priority bundles to show immediately, giving me larger blocks of uninterrupted time but with the knowledge that I'll still get notified of truly urgent stuff immediately.

Consistent Interface

It took me a while to realize just how valuable this is, but it's really great that the mobile and web UIs for Inbox are virtually identical. I don't have to have two different flows for handling e-mail on mobile vs desktop. The mobile UI is a tiny bit better because of the gestures a touchscreen interface can provide, but my process for using it is the same.

One common complaint about Inbox vs Gmail is that Gmail's more compact; you can fit a lot more stuff on the screen with the Gmail UI. I find that isn't a problem, because the Inbox workflow mostly eliminates the need to scan through a big list of messages visually, looking for something in particular. The need to do that arises mostly (for me, anyway) when I'm keeping a lot of stuff hanging around in my inbox. With Inbox, I don't do that. I snooze it or I archive it, so my inbox is empty nearly all the time. If I need to find something that I've snoozed or archived, I search for it.

Bottom line: If you're a heavy user of Gmail, you should really take a good look at Inbox. Odds are you'll never go back.

Science

The Science of 4th of July Fireworks 40

StartsWithABang writes: There are few things as closely associated with American independence as our willingness and eagerness to celebrate with fiery explosions. I refer, of course, to the unique spectacle of fireworks, first developed nearly a millennium ago halfway across the world. But these displays don't happen by themselves; there's an intricate art and science required to deliver the shows we all expect. So what's the science behind fireworks? Here's the physics (and a little chemistry) behind their height, size, shape, color and sound, just in time for July 4th!

Comment Re:My Rant For Years (Score 1) 260

n one sense of the term secrecy is in itself a hostile action...

Really?

Care to tell me what hostile act wearing clothes in public constitutes? Clothes, after all, cover up your body... keep it hidden from view. That's secrecy.

Wanting to keep something private isn't a hostile act... wanting to know something that somebody was trying to keep private can be, however.

Your line of reasoning parrots those who would say that if you've done nothing wrong, you have nothing to hide...

Except that almost everyone *DOES* have something to hide. Not because they've done anything wrong, but because they have things that are private or personal.

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