Specifying or selecting the best access control solution for your requirements can sometimes be a daunting prospect. There’s a multitude of products under the umbrella of electronic access control offering different levels of security and functionality for any size of application – from securing a single door through to extensive multi-site systems linked over the Internet. Today’s modern systems also offer much more than pure security, being regarded as an essential management tool and increasingly integrating with other building and/or personnel systems for a ‘total enterprise solution’.
Fortunately, help is at hand for the discerning specifier. PAC International has compiled its ‘System Design and Specification Guide’ for security consultants, but the CPD-accredited guide is also an invaluable resource for security managers tasked with choosing, designing or using an electronic access system. The detailed guide covers a range of subjects, from specification rationale and system design through to examples of system architecture and component location.
A good starting point for determining whether an access control system is appropriate for any application, and subsequently identifying the right system, is first to collect basic information and then conduct a site audit. First of all, though, be sure that you understand what is meant by the term ‘access control’.
Put simply, it is the use of devices or methods at various points to control the passage of people and/or vehicles into or out of an area or structure.
Electronic access control is the ability to restrict the entry or exit of an individual through single or multiple ingress/egress points (doors, turnstiles or car park barriers) using a reader (which accepts tokens, electronic keys or smart cards, or indeed any combination of such devices). Electronic access control allows an individual’s identity to be validated, and also allows that individual to be granted or denied access based on pre-programmed data (including time and date).
An integrated access control system is one that incorporates additional features, and can be seamlessly integrated with time and attendance, building management systems, alarms, staff protection, parking systems, environmental solutions and much more.
Integration allows individual systems to communicate with each other electronically, translating an event into an action. For example, as well as providing access control, an integrated system may provide alarm monitoring relating to CCTV and perimeter detection. This would allow the system to control cameras, making them pan or tilt to record movement or activity if an unauthorised person is trying to gain access. When such an event is recorded, an automatic emergency message can be sent (via telephone, pager or mobile telephone) to other personnel, or to a local or remote monitoring centre.
The system’s ability to automatically notify an operator when an emergency event is recorded can prove to be invaluable in ensuring an effective and timely response. This is also a very effective tool for protecting staff in any type of application.
Components of an access system
A typical access control system will be made up of five components: the ID device, the readers, the door controller, the door lock and the administration system.
The identity (ID) device – which may take the form of a card or token – allows an authorised user to enter or exit through a door (or turnstile/car park barrier). In the case of proximity technology, each device has a unique code that’s detected by the reader. Whether the user has an ID device or security code, it’s entered into the access control system through the reader.
There are many different types of reader and reading technology available. Most access control systems can handle a variety of reading technologies, including wiegand, proximity (non-contact), magnetic stripe, infrared, hands-free, bar code, biometric and smart card technologies.
The entry reader is usually installed on the wall by the door handle to detect the unique code (either from the ID device or courtesy of input by the user) and sends the code to the door controller. Different types of reader are available for a host of different applications.
What about the exit reader (for leaving a secure area)? Sometimes a reader is used on both sides of a door, controlling entry into and exit from an area. However, in most cases a Request To Exit (RTE) switch or button is used to open a door from the secure side. Anyone can press this RTE switch when leaving, and the identity of the person leaving will not be recorded.
A request to exit PIR (passive infrared) switch operates in much the same way as an RTE switch, the only difference being that no physical action is required as the door lock releases automatically when a person approaches the door.
There are a number of reading devices on the market, ranging from inexpensive low security keypads to high security proximity cards and sophisticated biometric systems. In ascending order (ie highest degree of security first), the technologies are: biometric, smart/proximity cards, watermarks, wiegand, infrared, magstripe, barcode and keypad PIN only.
Biometric systems, of course, make use of physical attributes such as fingerprints, retina scans and voice recognition for identification purposes. The significant benefit of smart cards is their ability to store data on the card and read/write information to the device’s memory. Typical applications include electronic purse, confirmatory biometrics and student library identity devices.
Proximity is the most popular form of ID device, mainly due to ease of use. The end user simply presents the ID device in the close vicinity of the reader to release the door. No contact is made between the ID device and reader, thus wear and tear is avoided. Proximity readers also have no slots or holes, making them resistant to vandalism and adverse weather conditions.
Watermark uses an encoded strip of film that’s placed onto a card. However, it’s far more secure than the magnetic stripe because it’s securely coded and is more difficult to copy. Wiegand cards, meanwhile, are manufactured with a wiegand ribbon or tape. This tape has shot wires embedded into it, each of them individually polarised such that they emit a code when passed through a magnetic sensor. An infrared ID device has a built-in battery, and is operated by pointing it at the reader with its button pressed (offering a long reading range of typically up to nine metres). Infrared reading technology is ideally suited for applications such as car park barriers.
Magstripe cards use an encoded magnetic strip laminated onto a PVC card. This is one of the most widely used technologies due to the low cost of both cards and readers. That said, magstripe readers are not suitable for harsh conditions. The exposed reader heads need regular maintenance as they can collect dust and dirt, and may be easily damaged. Magstripe cards can also become corrupted, worn out or bent and are easy to copy – as such, they’re not for high security applications.
Unlike the familiar supermarket-style barcodes, the barcode widely used in access control applications is invisible and read by an infrared reading head. These cards are inexpensive, but again are fairly simple to copy.
Last, there’s keypad PIN only or keypad PIN plus proximity access. Personal Identification Number (PIN) entry technology is one of the most common types of access control used today. It’s cost effective, but one of the least secure methods (simply because PINs become widely known unless they are changed frequently). However, if they’re changed too often people forget the code.
An alternative is PIN entry plus proximity.
Door controllers and hardware
The door controller is at the heart of any access control system. It’s the device that compares the user’s ID code with the information stored in its own database. If the code is valid, the door controller will unlock the door.
The main functions of the door controller are to: decide whether a person is allowed through a controlled point at a certain time or date, provide power to operate the lock, monitor doors for authorised access or doors left open, lock and unlock doors automatically at certain times, detect tamper conditions, monitor inputs which may be configured for extra alarm points and operate programmable relay outputs which send messages to other equipment (thereby translating an event into an action).
In reality, the doors of an electronic access control system can be secured with various types of electric locks, most frequently with either magnetic locks or electronic door strikes. Locks are available in two locking modes: fail safe (used in applications that require automatic unlocking in case of power failure – they lock when powered and unlock when power fails or is removed) and fail secure: used in high security applications, in most cases fire codes will require manual override for emergency evacuation of a secure area – they unlock when powered and lock when power fails or is removed.
What of the administration systems? Comprising hardware and software, they provide the end user with the ability to program, commission and manage the access control system. A PC is normally needed to run the software. Depending upon the size of the system, number of doors and/or sites and the software connectivity, a PC interface or Central Network Controller will be needed to administer ID devices.
Advances in technology mean that systems can now be run over a customer’s own computer network (ie Local Area Network or Wide Area Network) using the TCP/IP protocol. Again, the capabilities of the software and size of the system will determine the need for a CNC.
For instance, a CNC is not required when using the very latest 32-bit administration software and IP-compatible door controllers across LANs or WANs as the software allows a direct connection between the PC and the door controllers.
Identifying the need
There are various bits of information you’ll need to jot down to assist you in selecting the right system for the job at hand (the flow of building ‘traffic’ being a good case in point). For instance, what are the working hours at the site? Which department comes to work first? What kind of after-hours duties are typically performed on site, and do different employees use different entrances?
There is also the need to consider any other personnel – other than employees – who may need access, such as caretakers, cleaners, delivery personnel, emergency services and the increasingly important issue of staff protection. Are there staff in vulnerable places, or members of staff that work alone? Vehicle access and parking also need to be considered. Where do employees park during working hours, or after hours, and how many vehicle entrances are there? Is there provision for visitor parking? If so, where is it?
Once the need for access control has been identified, a more in-depth security audit should be undertaken by the in-house professional, including a detailed audit of the site(s), hardware requirements, door and software needs, systems integration possibilities, vehicle access and staff protection. The audit should include the following list of elements:
The design checklist
Once you have identified the physical features of the site, you can then begin to identify access requirements and evaluate the various options open to you.
Access requirements may vary considerably depending upon the application, but the following checklist is a good starting point:
(a) Size and location of system
How many access points are required on the entire system? How many people will use the access control system? Will the system cover one physical location (site) or more? Will the system control other locations as part of the same system, and how many other locations will there be? What are your future expansion plans in terms of both employees and locations?
(b) System administration and set-up
Reading technology – will ID cards or electronic keys be used? If using ID cards, will any company information (ie corporate logos) appear on them? Is it necessary to restrict access at certain times? Is a print-out required of card or key usage, including the times when they have been used? Should individual personnel photos appear on the card? Will the system need to be administered from a different location at different times of the night and, if so, how many locations?
What types of locking mechanisms will be needed? Is an audit trail (ie checking past changes to the system) required? Will the system run on the present company network?
(c) Physical system/alarm reporting needs
Will the system be required to report any alarm (eg door forced, fire door open or freezer alarms)? Will the system have to operate in extremes of temperature? Will car parking control be needed? Will the system incorporate elevator controls? Will the access system be required to work with CCTV protection? Will attendance reporting be needed? Will staff protection be required? Would any links to ‘time and attendance’ be advantageous?
By answering these types of questions, the end user will already have created an overview of what the access control system needs to offer in order to meet stringent operational requirements.
