CCTV (Closed Circuit Television) is the monitoring and recording of people, processes or property through the use of a camera and other related electronic security systems. This form of visual security can be sub-divided into analogue and IP (Internet Protocol) solutions.

When referring to a ‘physical’ Access Control system this typically includes locked gates, doors or barriers which can be opened using identity authentication methods such RFID access cards, pin codes, face recognition, finger prints or smartphones to allow entry to a building or certain area. This technology can also provide data to track how a building or site is being used, such as frequency and time-usage trends.

CCTV cameras are available in monochrome (black and white) or colour. The different types of cameras are Board CCTV cameras, Bullet CCTV cameras, Fixed Dome cameras or Vandal Proof cameras, Fixed CCTV cameras (also known as Static cameras), Zoom cameras, PTZ (Pan, Tilt, Zoom) cameras, High Speed Dome cameras and IP (Internet Protocol) Network Cameras.

There are 4 Types of Access Control

Discretionary Access Control (DAC)
With a discretionary access control system (DAC) the owner of the company can decide how many people have access to a specific location. Each access control point has a list of authorised users. Every time a keycard is swiped, a PIN is punched, or a fingerprint is scanned, the system checks the credential against the list and either allows or denies access based on the previously set allowances.

Mandatory Access Control (MAC)
On the other end of the spectrum, mandatory access control systems (MAC) are the most secure type of access control. Only owners and custodians have access to the systems. All the access control settings are preset by the system administrator and can’t be changed or removed without his or her permission.

Role-Based Access Control (RBAC)
Role-based access control (RBAC) is quickly becoming the most popular type of access control. Instead of assigning permissions to individual users like in a MAC system, an RBAC system works by assigning permissions to a specific job title. It cuts down on the time required to set up or change user access.

Rule-Based Access Control
Not to be confused with the other “RBAC,” rule-based access control is commonly used as an add-on to the other types of access control. In addition to whatever type of access control you choose, rule-based access control can change the permissions based on a specific set of rules created by the administrator.

There are several differences, some of the major ones being:

The NVR connects to the computer network along with the IP cameras.  The main advantage of this is that you can use the existing network infrastructure, meaning you don’t have to run wire from a home base location.
The DVR uses coaxial connections to each of the analogue cameras.
The NVR supports high resolution megapixel cameras
The DVR supports only cameras with VGA resolution

If the police believe that you have evidence captured on a CCTV system that can help with enquiries that have the right to obtain copies of the footage.  You do not have the right to refuse access to the images and should facilitate making a copy.

CCTV for the home usually needs to be priced keenly and be wireless.  Unless you are remodelling your house, it is very difficult to discreetly run cables to each camera.  There are many systems on the market now that are able to work wirelessly.   

Probably the most common fault is with the power supply.  Secondly, the connectors that transmit the signal can also be faulty.  With an analogue system a poor connection will result in a poor image or a complete loss.  With IP systems generally, you will have no picture.

 Blurry CCTV images can be caused by a number of factors.  The most likely cause is a dirty lens – cleaning the lens will fix this.  Older cameras require proper setup so that they are in focus both in daytime and night-time – proper back focusing of the camera will resolve this issue.

CCTV will work without the internet.  True CCTV systems do not connect to another network – this is why they are called a closed circuit.  Connecting a CCTV system to the internet does allow for remote access to live and recorded images but increases the risk of unauthorised access.   

CCTV system will generally default to record 24/7 when a camera is attached to the NVR.  Sometimes the recording schedule for a channel can be in the wrong setting – ie motion record or only during office hours.  Ensuring the recording schedule is correct will sort most non-recording problems out.