Priorities for Network Uptime in Video Surveillance
Understanding what measures are feasible and what measures are extremely expensive or not possible is a key element in planning your network uptime strategy. While there are numerous measures available, many are hard to justify financially or not possible with your existing system.
Fredrik Nilson offers an excellent review of strategies for minimizing downtime [link no longer available]. I encourage you to read it. Following Fredrik's article, this review offers some advice on measures that can cheaply and quickly make a difference in deployments.
Measure #1: UPS
Power availability issues are the most common problems in creating downtime yet easiest and cheapest to solve. UPS systems are one of the least expensive measures to combat this. The systems themselves are usually in the hundreds of dollars and they are simple to deploy. You do not even need to back up power for hours. Even a system that backs up power for 30 minutes or 1 hour can solve the most common field issues.
Measure #2: Line Conditioning
Brownouts and power spikes are two of the most significant issues in damaging and destroying video surveillance systems. Computers are electronic devices and they are designed to use a defined voltage range. If the voltage moves out of this range, the probability that your equipment will fail increases significantly. Clean power should not be taken for granted, especially for the conditions that video surveillance systems are deployed.
Line conditioning automatically regulates and adjusts 'bad' voltage into proper levels for your equipment. Moreover, line conditioning is commonly available as a feature of UPS systems. As such, it can be trivial to enable line conditioning by simply choosing a UPS with this built in. The price is modestly more, but not significantly and the benefits over the life of the system are significant.
Unfortunately, UPS and line conditioning are very commonly not used for video surveillance system components. It often is overlooked or not budgeted in. Making sure it always is will provide significant long term operational and financial benefits.
Measure #3: Video Management System Tolerant to Hard Drive Failure
Using RAID for redundancy is great but many choose not to use it because of increased costs. If you are not going to use RAID, it is still very valuable to ensure that the video management system does not fail due to a failure of hard drives.
You do not want to be in a situation where you do not have RAID and the failure of any hard drive knocks out your entire system. The resulting downtime can then be in days and the emergency service call can be expensive. There are two common ways to accomplish this and you should verify these are available if you choose not to use RAID.
1. The video management system runs on a separate hard drive from the video storage and is independent of failures of hard drives storing video.
2. The video management system runs on a flash disk while the the hard drives store video only. Since flash is very reliable, you can be confident that even if a hard drive dies the system continues to be functional.
Many other measures have strong potential to increase uptime but could be challenging to justify the cost to implement.
You may already have redundancy/ fault tolerant elements of your network. If so, you can simply leverage existing assets. However, if you need to upgrade or deploy yourself, the cost differential in enabling such features can be very expensive. For instance, using MPLS-VPNs can be very powerful but procuring the appropriate equipment and services to deploy can be a significant cost. It is best to determine what you can already leverage and review carefully the cost and risks of upgrading or new deployments.