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Master Keying

Master keying is the ability to use one key to open one or more locks that are not keyed the same. This is frequently found in commercial setups, like businesses, where a user may have a key to their office that can also open the bathroom, or a janitor may have a single key that opens every door in the building. It can also be found in apartment complexes where each renter may have a key to their apartment, and that same key can also open the main door into their building or other common areas. Master key systems can be extremely complex, involving multiple master, grand master, and sub master keys. We are happy to offer masterkeying for both our Abloy and BiLock product lines. For small setups masterkeying starts at only $15 per cylinder. For more details or to order masterkeying services, please contact us.

Standard Master Keying Systems

While master keying can be a great convenience, it can also introduce security vulnerabilities in traditional pin tumbler locks. Masterkeyed pin tumbler locks are easier to pick and bump, and even leave open the possibility of an intruder reverse engineering a master key for the system. Virtually all common master keying systems (Best Lock and Falcon for example) are very vulnerable to master keying exploits. While master keying does make picking and bumping simpler, the greatest risk is due to rights amplification. Originally released in 2002, Matt Blaze from AT&T Labs wrote a paper called Rights Amplification in Master-Keyed Mechanical Locks . In short, any user who has access to any lock in the system and a working key to that lock can fairly easily reverse engineer the Grand Master Key that opens all locks in the system.

Our Master Keying Systems

The BiLock and Abloy master keying systems do not operate in the same way as a traditional master keying system. They have far greater total possible combinations with only a slight compromise in security. BiLock key blanks are quite difficult to obtain, and keys are much harder to manipulate compared to normal keys, making it very hard to carry out a rights amplification attack. Abloy blanks are also exceptionally hard to obtain. The keys feature a very unique multi-axis cut system that makes them virtually impossible to manipulate. For very large master key systems, we recommend the Abloy product line due to its extremely versatile master keying possibilities. No matter how large the system, the master keying will not greatly reduce the security of the Abloy lock.
Security Snobs can help provide additional information and assistance to meet the needs of any master key systems you desire (small or large, basic or advanced). If you have any questions or would like a master key system quote, please contact us. For small master keying systems, pricing starts at just $15 per lock.
Master key systems can vary widely in scope from very small to very large systems. To start, Security Snobs can assist with small master key systems for average residential users. For example, you could have a padlock keyed to allow your house key to open the padlock. At the same time, you could also have a separate key which could open only the padlock and not the home. This would allow a landscaper access to your shed without compromising the security of your home. Rental homes, condos, and duplexes are good candidates for master keying because they can allow certain doors to be opened by all tenants while others can be opened only by one specific tenant. Masterkeying also allows locks to be changed for new tenants but still open with the same master key. Locking knobs are becoming more popular on master bedrooms. These can be masterkeyed to allow certain keys to open only the outer doors to the home, but the master key can open both the outer doors and the master bedroom. There are many more possibilities.

Master keying Example




In this example we have a small rental setup with 3 apartments. Each apartment has its own key that can also open the complex's front door. There is a property manager/maintenance key that can not only open the complex's front door, but also all of the apartments. On the right side of the chart we have the owner's home. The owner's child has a key that opens the front door of the house along with the padlock on the child's bike. There is also a worker key that will only open the door knob on the side door of the house but not the deadbolt. This way, workers can only enter through that one door, and only when the deadbolt is not locked. Next we have the owner's partner's key. This key can open all the doors of the house along with the padlock on the child's bike. In addition, this key can open the master bedroom door. Finally, there is the owner's key that can operate all the locks in the system.