Most companies have one goal in common: protect the premises against burglary, theft and unauthorised access as comprehensively as possible. Quite often, however, the actual implementation of this project is their weak point. The question that comes up first is: which access solution best suits our needs? One important choice is between online or offline access control – and what actually is the difference?

Unauthorised access to critical areas can have serious consequences: Stolen equipment or compromised data can lead to financial penalties, long and expensive recovery processes and loss of public image. A secure and efficient access solution is key. But which solution is best for you?

Access control keypad outdoor on brick wall with man's hand pressing button

Standalone access control

Offline, or standalone access control systems for smaller projects can be implemented easily, quickly and at no great cost. Only basic control is required: a reader/keypad, a proximity tag/card, and a power supply. Each door can only be unlocked with a tag or card which has been issued to the user authorised for that specific door access.

Doors cannot be centrally managed and controlled. Each tag is manually added to each individual door controller that the tag is required to access; as opposed to online access control that allows you to change/update authorisations from a computer or smartphone.


  • Simplicity – no computer access required
  • No congregated wiring system
  • Little to no maintenance
  • In the event of a break-in, could be more easily disabled
  • Affordable for small budgets
  • No data reporting for accountability
  • No specialist training needed for end user
  • No remote/centralised access; each tag must be memorised on each controller individually
A woman with red hair sits at a laptop concentrating on what's on the screen, with a pen in her right hand ready to take notes

Online access control

Centralised door access systems are scalable. Some of the benefits of centralised technologies include the creation of different user profiles for different access points, as well as better visibility and monitoring though the activity log. Thanks to centralised systems it is also possible to integrate additional security services such as alarms and CCTV. We can also take advantage of the advanced functions of centralised systems to control the capacity of certain spaces and locate specific individuals.

With online access control solutions, all data is managed in one central system, such as CDVI’s ATRIUM software. User profiles, authorisation levels, and tag/card management can all be administered from a computer or smartphone. Advanced features can allow external service providers to enter the premises for limited periods if required, and all successful and unsuccessful entries/exits are documented for later analysis.

Through ATRIUM, security managers benefit from the freedom to manage and monitor access from anywhere, in real time.


  • More secure as hardware is monitored and set up internally
  • Can become costly
  • Centralised control
  • Assisted training is needed
  • Higher capacity of users and doors
  • Maintenance is more advanced
  • Simple & user-friendly software
  • Can be more invasive to install the required hardware
  • Remote functionality
  • Stored data for accountability


Online access control allows facilities managers to monitor their systems and buildings remotely. Remote monitoring makes it easier to keep an eye on security no matter where you are. If all you need to access the system is a web browser and an internet connection, you can log in from anywhere on any device.

The right solution for you

It’s always been essential for security managers to be able to remotely access and monitor building management platforms, but the pandemic has significantly exacerbated that need. With more people than ever now working from home and a sharp increase in flexible working hours, the traditional mass ingress and egress at 9:00am and 5:00pm have largely disappeared.

Most companies nowadays want to be able to manage as many subsections together as possible. In regard to access control, a mix of online and offline as an interconnected solution is also possible. Different areas within the building may have different security requirements.

While entrances or critical areas need real-time monitoring including alerting, other areas in the building may have lower physical security needs. A standalone access control system may be suitable as an extension to an online access control system if lower costs and quicker installation are business priorities.

A flexible, scalable access control solution for up to 500 doors

Find out more about ATRIUM access control. Backed by a unique ten-year warranty, ATRIUM offers the peace of mind of a reliable system for you and your customers.