Video Surveillance 101

Use this to familiarize yourself with the basics of video-surveillance systems, from older to recent technologies. Some clients may use an older system or component to address a specified need. For others, recent systems are a better solution. The right configuration depends on a client’s circumstances, size, goals, budget or what problems need resolution.

Types of Systems

(Older to newer)

VCR-based Analog CCTV – Analog cameras are connected to a video cassette recorder which stored video on cassettes. All signals and devices were analog. CCTV stands for closed circuit television. In addition to the VCR, a quad/multiplexer device enabled views of four separate images on one monitor or record more cameras on one VCR. The quad/multiplexer can assign a given camera to specific monitors, enabling control-room operators to view multiple scenes simultaneously on separate monitors.

DVR-based CCTV – Arriving in the mid-1990s, this system connected analog cameras to a digital video recorder (DVR), which became the recording medium instead of the VCR. Analog feeds were digitized and compressed for storage. This eliminated the need for taped cassettes and users could search recorded video more quickly. Additionally, the DVR enabled quad/multiplexer functionality.

Network DVR Analog CCTV – As time moved on, the DVRs featured an Ethernet port for network connections. This made possible both remote viewing on PCs and system operation. In these systems, the main components are analog cameras, DVR, network switch and PCs in addition to coax and twisted-pair cabling. Although it represents a technological advance, the DVR had limitations regarding maintenance, upgrades, virus protection, etc.

Video Encoder-based Network Video Systems – An open platform, this system uses a video encoder (or video server) to digitize and compress video sent by analog cameras. Video is sent over an IP network via a network switch to a PC server. This server runs the video management software or VMS and handles the recording function with better scalability.

Network Camera-based Video Systems – An entirely digital system, this development uses IP or network cameras, which digitizes the images within the camera; this digital format remains throughout the system to deliver strong and consistent image quality. Video is transported over an IP network using switches. The PC server handles recording. Video analytics, megapixel cameras, wireless functionality, ability to pan, tilt, zoom and other functions are accessible over IP.

Video Surveillance as a Service (VSaaS) – An on-demand, cloud-based video management system (VMS) compatible with a range of analog and IP security cameras. Unlike traditional systems, VSaaS does not require installation of an operating system, application software or the configuration of routers and cameras. There is no need to set up storage servers. Users can connect most existing cameras to a small bridge appliance, which enables connection to the cloud-based VMS. Cloud and on-site recording are available.

Note: Web cameras are typically used for such applications as Teams, Zoom or Skype video. These are not the same as IP Network or analog cameras. They don’t have recording functionality. They operate only when connected to a PC or laptop. Software must be installed on the PC to run the camera.

IP Video Recording Systems

These days security cameras are “pretty much everywhere.” Unless hidden or camouflaged, they’re easy to spot as well. Day or night they capture footage continuously, including our own faces or vehicles! For camera operators, what happens after the images are collected is where the “rubber meets the road” regarding effective security management.

Operators need a proper computer system to record, store and manage video feeds plus information from other security components like alarms or door controls. Three primary options are available:

  1. Video Management Systems (VMS)
  2. Network Video Recorder systems (NVR)
  3. Cloud-based Surveillance as a Service (SaaS)

 

Note: DVRs or digital video recorders, are excluded in this section since they are suited for home security or businesses with only minimal security needs. Click here for a DVR overview.

To help end-users determine best options, the following provides basic information about each system.

Video Management System (VMS) — Although the entire system is comprised of hard devices like cameras, card readers or other security components, our industry classifies VMS as a software-based solution. The reason: these systems rely on video-management software that must be configured onto general-purpose servers running Windows or Linux operating systems. These servers are tasked specifically to record, store and manage video footage (plus other components like access-control devices).

Additionally, network switches, routers and other devices connect cameras and other components to the server. In some cases, a server with a special card performs video management while a companion model handles archiving. The later is called a network attached storage (NAS) device. As mentioned, client software enables video footage viewing and management.

  • VMS advantages — VMS offers a unified platform for managing all surveillance cameras with limitless scalability. Most VMS systems have open architecture, allowing customers to select from countless camera options. AGC’s VMS unifies an entire security ecosystem under a “single pane of glass” to run investigates with amazing speed, proficiency and less operator stress. Click here for more information about our single-pane-of-glass method.

 

Network Video Recorder (NVR) — NVRs use an appliance already embedded with an operating system and application software dedicated solely to recording and storing video footage. Thus, we define NVRs as hardware-based solutions. NVRs are comprised of a processor, memory, storage devices and interfaces to record video over a data network (unlike DVRs that require a direct cable link from the camera to the recorder). NVRs are proprietary per the manufacturer’s standards. Unlike VMS, NVRs are limited in how many new cameras can be added once the system is installed. So total number of cameras must be determined before investing in an NVR solution. A typical example is deciding between an 8- or 16-channel system.

  • NVR advantages — Since it’s a hardware-based system using a dedicated appliance to store and manage footage, NVRs are, as a rule of thumb, less expensive than VMS systems. Being software-based, VMS is generally more expensive because a dedicated server is required to store and manage video, which can be costly to design, implement and maintain.

 

Surveillance as a Service (SaaS) — SaaS is an on-demand, cloud-based video management system compatible with a range of analog and IP security cameras. Hosted video eliminates the need to install an operating system or application software at each site. Configuration of routers and cameras plus deployment of storage servers are eliminated as well. Clients plug in a small box to connect their analog or digital cameras and can auto-configure the cameras.

  • SaaS advantages — VsaaS has very low upfront capital expense with a predictable monthly operating cost. Cloud-based surveillance can benefit clients managing cameras at multiple sites, such as branch offices or franchise locations. In these settings, handling multiple video servers often becomes cumbersome, costly and inefficient.

Sources: 1) Bulleted information based on Intelligent Network Video by Fredrik Nilsson of Axis Communications, CRC Press, Taylor & Francis Group, 2009. Updates based on August 2020 interviews with Advanced Global Communications. 2) Video Surveillance as a Service (VSaaS) based on 2019 interviews with Advanced Global Communications.