Onsite Vs. Offsite CCTV video image storage
Making an educated decision when choosing between local or cloud-based CCTV image storage
Escaping the hype and making an informed choice
Cloud computing has transformed the way businesses and organisations of all types provision for their technology requirements. Across the broad range of IT services which may need to be made available to the workforce to enable operational capability, there is likely to be a cloud solution for practically any requirement.
One of the big advantages of the cloud is it enables technology service to be outsourced to a Managed Services Provider (MSP). For any given IT requirement this eliminates the need for servers and storage onsite at the place of business. Rolled out across all of an organisation’s systems this negates the need for on-premise server and storage infrastructure.
For some this is highly attractive as it enables the headaches of IT to be offloaded and enables the workforce to focus on core business activities. This frees IT workers to concentrate on higher value activities such as adopting a more customer facing or strategic role.
The convergence of security systems and computer infrastructure has been going on for well over a decade. Today’s IP CCTV systems use networked digital cameras and include on-premise video servers to record images.
There is significant interest about the use of cloud-based systems to store images uploaded from the business premises. However, this is over-hyped and it is not as straight forward a choice as the marketers of cloud-based systems might have us believe.
Indeed in some respects, onsite versus offsite CCTV storage is a little like comparing apples with oranges. The best advice is to understand the pros and cons of each approach and to make the right choice to meet the operational requirements of your business. Here we help those who are considering the best place to store video images make the right choice.
The power of IP CCTV
IP CCTV is a powerful technology. This is because of two key factors. It enables the capture of Hi-Definition (HD) images to obtain greater detail. As a consequence, HD improves the ability to obtain intelligence through video analytics.
By way of contrast, legacy analogue systems deliver relatively poor resolution. Analogue images may be digitised to enable analytics to be applied. However, digitisation cannot improve resolution. Consequently, obtaining intelligence from footage captured by analogue cameras is always limited.
In any project to replace or upgrade an existing CCTV system or commission a new one, the advantages of IP CCTV are compelling.
The truth about CCTV image storage
The simple truth about whether to store CCTV images onsite or offsite is that it is all about the amount of image data generated and network bandwidth.
Typically an IP network with local, onsite storage is capable of providing Gigabit-per-second (Gbps) network speeds. This is the performance needed to handle images from multiple high definition (HD) cameras deployed across a site.
Average and peak bandwidth of a 2.0MP IP CCTV camera
A standard HD camera rated at 2 megapixels (MP) delivers an image resolution of 1920 x 1080, the common ‘HD’ rating of today’s flat, widescreen televisions. Essentially every frame is composed of 1920×1080 pixels or 2,073,600 dots. (This is rounded down to 2 million, hence 2MP).
Compression is applied to ‘squash’ the data. To give a better idea of what this means, consider the term JPEG, which is familiar to many. JPEG is a compression technique that enables reductions in still image file sizes. H.264 is the video equivalent and the most widely used compression standard for CCTV images.
Preserving the detail captured by a 2.0MP IP CCTV camera by not overly compressing the images and assuming a reasonable frame rate of say 6 images per second means transferring the camera image data to the recording devices, typically a Network Video Recorder (NVR) or a video server, requires an average network bandwidth of 3Mbps.
However when there is movement or a complex scene including variables such as trees, clouds, low light image noise, rain and so on, the bandwidth may peak at 12 Mbps. H.264 is a variable bitrate (VBR) compression technology that applies an appropriate amount of compression to preserve detail and is responsible for the fluctuation from 3Mbps average to 12Mbps peak stream bandwidth.
Local storage network requirements
Typical multi-camera systems of some IP CCTV environments might be:
|Size||Type of environment||Number of cameras|
|Very large||University campus||1000|
So for a mid-sized system consisting of 2.0MP cameras the total bandwidth requirements are:
- Average – 80 cameras x 3Mbps = 240Mbps
- Peak – 80 cameras x 12 Mbps = 960 Mbps, (c. 1 Gbps)
1Gbps network bandwidth approximates to the capacity to transfer a 125 MegaByte (MB) file every second. So for a mid-sized site, Gbps network performance is adequate for handling the images from all the cameras at times of peak activity during business hours.
Cloud storage network requirements
For a cloud-based system to store the images from 80 x 2.0MP cameras, the basic maths above doesn’t change. What does change is the cost of uploading the CCTV streams to the cloud storage system.
One leading UK business-class broadband service marketed as ‘Ultrafast’ only provides 15Mbps upload speed as standard. Mid-sized business and organisations wishing to put their CCTV images in the cloud would need to install special fibre optic network links to carry the traffic.
On average, line rental charges put the annual transmission costs at 3 x the cost of storage hardware. Essentially, by the time the hardware of the cloud storage platform reaches the end of its warranty, the customer would have paid for the storage 10 times over. This doesn’t include costs for installation, routing devices and set up. Installation may simply not be possible for many rural or sites situated in unfavourable places, badly served by ISPs.
Proprietary cloud CCTV services
Despite the limitations of network connectivity cloud-based services are available and are heavily marketed. To make these viable, compromises have needed to be made. This means there are often a number of performance limitations associated with cloud-based services which may mean such an approach is unsuited to the needs of your organisation. These include:
- Analogue-only cameras
- Proprietary adapter hardware required for each camera
- Limited resolution, typically 720 x 480 (D1)
- Inability to reveal detail or yield intelligence from analytics
Onsite CCTV camera and data security
One of the commonly cited benefits of cloud-based services is that they provide better IT security than onsite solutions. However, this assertion is something of a red herring that should not go unchallenged.
Security breaches of cloud-based systems are widespread. Some of the biggest names in the technology industry have had their online services hacked, including Sony and Apple.
Onsite systems that are correctly installed and operated in line with best practice for information security and the guidelines of the ICO (Information Commissioner’s Office) provide the level of security required to protect data and meet regulatory requirements.
Help to choose the right CCTV storage for your business with iC2
When it comes to choosing whether onsite or offsite CCTV storage is right for your business, iC2 provides the consultancy and impartial advice to enable you to make the right decision.
Simply contact us today for a preliminary chat to discuss your requirements.
To find out more about issues which influence obtaining the right CCTV services for your organisation click here for the blog ‘Beware poor value CCTV and security system maintenance contracts that carry hefty callout and labour charges’.