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Coming Up With A Pin Code
These padlocks and digital locks require a PIN code meaning that 'information' becomes the key. This is really little different from how locks worked previously, and it would be possible in theory to create a code representing the ridges on the key with no real difficulty. However, when you have a code for a door, this then means that your security entirely relies on the strength of that code making this highly valuable data. Like any data that you might want to protect on a computer, this data can be almost 'encrypted' allowing you to code your code in such a way that it will be hard to guess, or won't have to be written down.
Most codes will require four numbers or six numbers. This can be hard to remember though and it leads to many people making the mistake of choosing codes that are somehow personal to them so that they won't forget them. While this will indeed work, it will also make it much easier for others to find out your password. If you use a birthday of yourself or someone in the building then this is information that anyone will be able to obtain fairly easily from records etc. At the same time dates generally have certain elements in common - they are likely for instance to have a 0 as the first and third digit. At the same time if someone can guess your age, or the ages of people close to you, then they can give a ball park figure regarding the last two digits. Phone numbers are even worse.
The really highly secure PIN codes are based on something unexpected but still memorable. You can apply rules here to memorable data - for example making it your birthday by in an unusual date format (such as DD.YY.MM). Similarly you could make it phone number but one that is illogical, and perhaps a random selection of the number (such as the area code + a couple of digits). It's easy to remember it, but no one will guess it!
Finally, the very best codes will change meaning they're impervious to spying and to guessing. To get your numbers to change, try basing them on temporal information such as the current date + four days. No one will guess this, and everyone will know what the code is (who is meant to) without being informed.
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