Electronic Physical Security Design
This installment of Security for Worship environments will focus on the electronic aspects of physical security design. The last issue focused on physical security design in general. We learned that security system design is a process that includes the definition of objectives, the initial design, the evaluation of the design, and a refinement of the design. Those steps also apply to electronic physical security design. The key is to have the electronic aspects work in unison with the other physical security items. Of course, as mentioned in other articles, the designer needs to balance an open/inviting environment with an environment that is relatively secure.
Electronic Physical Security
The physical non-electronic aspects that need to work with the electronic items include elements such as fences, doors, windows, barriers, procedures, and communication devices that combine into a comprehensive protection system to achieve the protection objectives. The resulting system design should meet your objectives within the operational, safety, legal, and economic constraints of the facility. Once the designer has performed the overall physical security design, the next major decision is to determine what electronic systems to use and how to integrate them into the system.
Electronic security systems are generally divided into two areas: Access control and Video surveillance.
Access control, in general, means controlling access to a port of entry in a physical area.
The five main parts of an access control system are:
Access credential (such as a card)
In addition to performing basic lock and key functions, access control also establishes and controls specific access privileges for each person and each door within the facility. Real-time monitoring and event-generating alarm software functions can provide a very high level of security. An effective access control system should be able to integrate with the following elements: Automatic door unlocking/locking system, Electronic tracking system, CCTV interface, ID badging (photo) and visitor management systems.
How does an access control system work?
An access control system grants or denies access or egress based on the correct identifying information presented as:
A number entered on a keypad
The encoded information of an access card scanned by a card reader
A biometric attribute
Or a combination of any or all of the above
The microprocessor in the reader transmits the information to the controller, which evaluates the validity of the request. Access or egress is then either granted or denied based on whether the information can be verified against a stored authorization profile. This process usually takes a couple of seconds or less. These profiles are designed to provide independent access rules for each person at each entry point.
The profiles define the ability of the encoded card number to gain access based on any number of the following criteria:
Time of day
Day of week
Previous events (i.e., mantraps, anti-passback controls, etc.)
If the information passes these checks, the secured door will unlock electronically. If the information is invalid, the system response may be to simply not grant entry, or it may also initiate CCTV recording, alarms, or dispatch physical guards or the police to the site.
Another key feature to a centralized Access Control System is the ability to create an audit trail for all controlled access points. For unique authentication devices facility personnel can review each access credential used to gain entry at any particular point at any time in recent history. So for example, if a laptop is found missing in a secured area, staff can review the security system logs to determine who gained access to the space between the time the laptop was in place and when it was found missing. Inherent with this feature is the understanding that protecting these access credentials is extremely important – exactly like a personal credit card – and should a person be fired or a card go missing it must be immediately reported and the authentication profile must be deactivated.
More advanced access control systems also have the capability to integrate a number of facility control functions, including alarm events, on-line CCTV monitoring and recording, photo verification, photo imaging and badging, multiple technology cards, HVAC control and management, and automatic elevator control. A truly integrated access control provides a central point of control, from a local or remote location, that offers a unified approach to an electronic infrastructure system.
A term commonly used to describe electronic physical security is intrusion detection. Intrusion detection is defined as the detection of a person or vehicle attempting to gain unauthorized entry into an area that is being protected by someone or something that is able to authorize or initiate an appropriate response. Intrusion detection systems consist of exterior and interior intrusion sensors, video alarm assessment, entry control and alarm communication systems all working together.
A subset of access control is perimeter protection. Perimeter protection simply means to protect the perimeter of the site. Common methods of performing this function are installing door contacts on perimeter doors, providing motion or linear beam detectors outdoors, or installing detectors on fences. Like other aspects of electronic security items these need to be integrated with physical items such as fences, walls and any other physical barriers. Again, the balance to maintain a welcoming environment must be weighed against the need for a secure environment.
An area that has been experiencing greater acceptance recently is Biometrics. Biometrics is an automated method of verifying or recognizing the identity of a living person based on a physiological characteristic. The following types of biometric devices are commonly used: Hand Geometry, Fingerprint, Voice Verification, Facial Geometry, Signature Dynamics, Iris Recognition, and Retina Recognition. The current usage is impacted by not only the technical development but also the acceptance by people to the particular type of device. For example, some people feel that iris recognition is too intrusive and are uncomfortable using it. These types of devices are typically used in areas where security needs are very high such as data centers or government facilities but are gaining acceptance in other areas as well.
The basic components of a Video Surveillance system are capture devices (cameras), switching devices, storage devices and viewing devices. Viewing devices can facilitate real-time monitoring of cameras or playback of archived video footage.
Cameras fall into two main categories: fixed cameras and moving cameras. Fixed cameras stay in one position until manually moved, while the position or focus of moving cameras can be changed via preprogrammed events or remote commands. Moving cameras include Pan – Tilt – Zoom (PTZ) cameras, and PTZ dome cameras (which can rotate 360 degrees). Each camera features different options for lenses, format, and housings. A camera’s lens can be designed for distance (for piercing long areas) or wide angle (to capture an entire room) or close-up (for facial recording). The format of the camera may be optimized for low-light conditions, day-to-night conditions, black and white images, or color images. The housing of the camera may be tamper-proof, appropriate for indoor or outdoor conditions, environmentally controlled (no fogging or freezing) or bullet proof. There is no perfect type of camera for every situation, and the needs for video monitoring and recording must be balanced with the facility design, monitoring strategy and overall budget.
The images captured by the cameras are displayed on a monitor. Two kinds of devices are used to control which camera’s image is seen on the monitor: matrix switchers and multiplexers. A matrix switcher uses a matrix (or grid) to determine which camera will display on which monitor. A multiplexer divides a single monitor into multiple panels, in which a different camera image can display in each pane. Additionally a sequencer can be used to step thru different cameras for a predetermined length of time.
Operator monitoring of the video in real time provides the highest level of security but it can be costly to employ a guard to watch all of the cameras all of the time. This is usually beyond the needs of a worship environment. However, staff personnel may be asked to provide some part time monitoring of a camera placed at a strategic location such as at the front door. Further, with the cost of hard drive space dropping, as better/less expensive products are developed, the amount of video images usually stored is increasing. Where it used to be common to store images for a week or two, users are storing images for a month or more.
Most modern image storage devices utilize digital hard drives as apposed to the older VCR tapes. The hard drives allow much quicker retrieval times and are obsolescing the use of VCR tape storage devices. Digital Video Recorders (DVR) build on the functionality of a CCTV system, providing stored visual documentation of access events. While the CCTV system passes a constant stream of video to the DVR, the DVR unit only saves the video that is associated with an event-such as an intrusion or critical alarm. In addition to being proactive, DVR technology offers features such as watermarking and digital motion detection. Watermarking is a method of placing a calculated number within each digital image. If the image is changed, the watermarked number changes to reflect the tampering. Digital motion detection allows CCTV cameras to become motion detectors.
Each image in the video stream is compared to the previous image, with the system looking for any change that could represent motion. With digital motion detection, “masks” can be setup for each camera, blocking certain areas from being compared. For example, a window looking out on a busy street could be masked, allowing the camera to continue monitoring the rest of the room for motion.
The convergence of computer systems and the CCTV worlds continues, yielding newer DVR systems where all of the camera monitoring occurs across Ethernet local area networks, with images monitored on desktop personal computers. These modern digital devices (IP-based DVR’s) can provide cost savings for smaller CCTV systems, reducing or eliminating the need for matrix switchers and video monitors, but note that the reliance on PC platforms has inherent drawbacks and reliability issues.
System Design Guidelines
In general a security system performs better if detection is as far from the target as possible and delays are near the target. Detection can be in the form of a motion sensor or a camera. Delays are things like fences or doors that delay an intruder.
In addition, there is a close association between detection and assessment. The electronic system designer should be aware that detection without assessment is not protection. Video surveillance without active monitoring and human response is a prime example. A church has unique challenges in that it needs to be an open environment and friendly to visitors and yet offer the appropriate level of security. A common approach is to design the electronic security devices to be more discrete. For example, surveillance cameras could be concealed, not exposed, and door contacts can be recessed, not surface mounted. In this way people’s attention is not drawn to the security devices.
This article introduces the use of electronic security systems into the overall security system design. It is important to ensure that the electronic systems work together with other aspects of security to ensure a comprehensive system. The process stresses the use of integrated systems combining people, procedures and equipment to meet the protection objectives. Following are a Glossary and three Checklists’ for your use in designing security systems with electronic components.