My idea for unpickable lock

[iv81]

That aside, yes, it would take a butt-load of thermite to melt through a lock in a matter that gave you access. I'm sure you could severely damage the lock with a small amount, but you wouldn't actually gain access.

A torch would be a better solution there.

But if speaking of a forced entry, the doorframe, hinges and the door itself play a better role of effective means of entry. I'll stick with the door lock for now.

[Omikron]

6. not use a lock that relies on the proper change in order to operate

I guess it's not for everyone. Tell me which lock you preffer then. I'm highly interested.

No offense iv81, but your idea, although somewhat original, is absolutely inconvenient.

A simple digital keypad or a combination lock would achieve far better results, based on the same concept. Both combination locks and your "change lock" operate on the same concept: security through obscurity. The only security provided, is that only you know the correct amount of change in order to operate the lock. A combination works the same way.

However, your system has a fatal flaw that the combination lock does not, in that there is no particular order in which the change is counted. A keypad or combination lock would require the correct numbers, but presented in the correct order. Mind you, I'm sure you'd be able to modify your change lock in order to do this, but I think the point is made.

Honestly, as much of a techie as I am, I hate electronic locks. I know how electronics fail, and I am always wary of using an electronic means of access control for extended periods of time. I would pick a well designed mechanical solution over a glitzy electronic one, any day.

[workstation]

iv81,

I like the concept of a lock that takes the key (coins, in this case) away from the user for processing, then returns a different, but functionally identical key (loose change), if the combination is incorrect. This would prevent impressioning.

So, you has some aspects of a good idea, but probably not the ones you were thinking of...

As an aside, if you cast the thermite with a binder, you could make thermite coins - a possible forced entry method!

I love thermite!

[Omikron]

As an aside, if you cast the thermite with a binder, you could make thermite coins - a possible forced entry method!

I love thermite!

Actually you can use red gum and alcohol in order to bind thermite into whatever shape you want. It burns a bit slower, but the reaction is far more controlled. So yes, this is possible.

[iv81]

I see your point Omikron. But not to sway you in or anyting, although I agree that numerical combination locks have their advantages through ease of use, they're also prone to attacks since their main components lay on the side of door where they are likely to get damaged, shoulder overlooked or finger traced with IR dust. the change locks can have propper filters installed to prevent much damage or unnecesary items put in. As far as bigger chance of electronic failure for security means as opposed to mechanical well I would't bet on it much either. Most business/home security alarms come with electronic keypads to activate or deactivate them. Most laptop failures for example are related to problems in devices sich as hard drives that are mostly mechanical. I've already provided solution to electronic blackouts for this or such electronic locks on last post of page 1 in this thread for generating electric current. Although the only possible destructive method I can think of to kill such locks would be using EMP.

By the way, I'm waitng to hear what you'd preffer on your door. Aside from electronic locks. Any mechanical one that you use?

[iv81]

So, you has some aspects of a good idea, but probably not the ones you were thinking of...

Are you thinking what I'm thinking...?

Key coins! (custom made coins with teeth on end) or posibly single key coin that gets inserted like a cd in a computer cd rom drive. If the key coin bay is not closed the lock will not open. (bay itself also acts like a key, even the plate to prevent outside manipulation)

[iv81]

Hey come to think of it, it's possible to use activated bar codes kind of like those square ones UPS uses on their packages to scan codes and voila. Ofcourse to prevent tampering, the laser will stop scanning once wrong bar was used 5 over times for maybe 20 minuite cycle period.

[iv81]

Maybe a modem key could also work, the key and door lock would both be modulator and demodulator to pass throguh cryptic digital keys. Oh the possibilities.

[iv81]

I would add this to the above post but I do not have the edit permission.

If anyone uses a USB flash drives, they kinda look like keys. Those can have a certain file that electronic locks can read, the file would be completely an encrypted binary or just a text file with a key, the hashing algorithm could be that of a standard MD5, they key would use insert once, trigger once reads to prevent bruite force attacks. Just an idea.

The backup of the key file ofcourse could be stored safely somewhere on the net in a strongly encrypted archive file or passed around to guests. The lock can be programed using a master key file that if used from inside, the newer outside key code would be accepted. A key file would be able to store a limited number of keys (around a 100) for obvious reasons. Anything more and the lock would reject it.

Anyone likes this idea?

[Omikron]

I would add this to the above post but I do not have the edit permission.

If anyone uses a USB flash drives, they kinda look like keys. Those can have a certain file that electronic locks can read, the file would be completely an encrypted binary or just a text file with a key, the hashing algorithm could be that of a standard MD5, they key would use insert once, trigger once reads to prevent bruite force attacks. Just an idea.

The backup of the key file of course could be stored safely somewhere on the net in a strongly encrypted archive file or passed around to guests. The lock can be programed using a master key file that if used from inside, the newer outside key code would be accepted. A key file would be able to store a limited number of keys (around a 100) for obvious reasons. Anything more and the lock would reject it.

Anyone likes this idea?

iv81,

Although creativity is good, there are currently far better alternatives to the systems that you propose, including many RFID or RF based solutions that use two-way authentication and whatnot, etc.

I like your enthusiasm though!

[Chrispy]

We're not bagging you iv81. This site is a kind of 'Chinese Parliament', so don't take anything we say to heart. We do like your enthusiasm. Welcome to LP101.

[iv81]

iv81,

Although creativity is good, there are currently far better alternatives to the systems that you propose, including many RFID or RF based solutions that use two-way authentication and whatnot, etc.

I like your enthusiasm though!

Hope you know RF or RFID are prone to man in the middle snoops/attacks.

Kind of like WEP keys being prone to broken on a wifi network.

[iv81]

We're not bagging you iv81. This site is a kind of 'Chinese Parliament', so don't take anything we say to heart. We do like your enthusiasm. Welcome to LP101.

I understand. And thanks.

[Omikron]

iv81,

Although creativity is good, there are currently far better alternatives to the systems that you propose, including many RFID or RF based solutions that use two-way authentication and whatnot, etc.

I like your enthusiasm though!

Hope you know RF or RFID are prone to man in the middle snoops/attacks.

Kind of like WEP keys being prone to broken on a wifi network.

Yes, yes, I know of the type of attacks you speak of, but the current generation of systems are in fact NOT prone to this type of attack, although the details of these systems are outside the scope of this forum. I may be a bit terse sometimes, but I'm not unaware.

[digital_blue]

Again, love the creativity involved here, but I'm not seeing all that much in the way of a practical solution. I have to say I think the idea of a coin operated lock is really not very practical, and bordering on the edge of absurd. Making funky coins with funky edges, well, I'm not sure what that accomplishes except to create a new style of key, of which you would have to carry several at once in order to activate the lock. It does not seem very convenient to me to have several "loose keys" rolling around in my pocket.

If one were to go to that extent, there are some very very secure systems in existence that would provide a high level of security. The only reason we don't all have them on our doors is cost.

There is, perhaps, a little merit in the idea of a USB thumb drive, but even this has its own issues. Any digital system that operates on a challenge/responnse model opens itself up to attack. This is why there is always a need for lockout periods when incorrect data is given (3 wrong entries, etc).

Another big problem with a thumb drive approach is the issue of having electronic contacts exposed to the elements. I suppose you could say that you could house this reader in a protected box with a weather-tight cap or something, but then I would ask you to envision yourself coming home with a couple bags of groceries and a couple young children in tote, and then ask you how you feel about this new system.

The challenge, of course, is always to increase security without compromising usability - something I'm not sure you've accomplished just yet - and find yourself at the end of it with a good, reliable, and convenient product that people will wish to use. I think your ideas thus far would be a tough sell.

Again, I do like the enthusiasm, so please don't take my comments personally.

Cheers!

db