There are various types of secure door entry systems available, each with its own advantages and disadvantages. Here are some common types:
Key-Based Systems are simple and inexpensive, easy to understand and use, but keys can be lost or stolen; duplication is possible; access cannot be easily revoked without changing locks.
Keypad Systems offer PIN-based access with no need for physical keys, thus making it easy to change access codes. The simplicity of codes can make it easy for PINs to be shared or guessed; keypad buttons may wear out or be susceptible to tampering.
Proximity Card Systems are convenient and easy to use and cards can be quickly deactivated if lost or stolen and are less prone to wear and tear. The downside is that cards can still be misplaced or stolen and some proximity cards can be cloned.
Biometric Systems are highly secure and difficult to replicate with no need for physical tokens or passwords. This simplicity comes at a cost though and biometric machines are not cheap. Also some biometric methods may have false rejection or acceptance rates and can also raise privacy concerns associated with storing biometric data.
Intercom Systems allow communication with visitors before granting access and can be integrated with video surveillance. Residents have to be home and manually verify visitors.Mobile App-Based Systems offer convenient access via smartphones with the benefit of offering remote access for deliveries and other visitors. These benefits do depend on smartphones and internet connectivity.