Not to be overly simplistic, but when deciding on a DVR for your surveillance system; you will need to decide if you want to go with a PC based model or a standalone unit. To make this decision a little easier; let’s look at what each of these are and what benefits they provide.
A standalone digital video recorder is a unit that is made specifically for one purpose; which is to capture, record, and store your surveillance footage. These units usually use a Linux based operating system that is designed with whatever features the DVR needs to perform.
With a standalone DVR you have a stable and dedicated recorder that can take your various surveillance cameras and store their footage for later viewing. Furthermore the hardware is all installed to compliment one another for this specific task.
Linux operating systems are less vulnerable to viruses, and since the DVR wont be accessing the internet on a regular basis (beyond serving up video for remote access); your chances of getting a virus that will clog up your system is very small.
Standalone DVRs can cost a bit more than it would to make or buy a PC based DVR that runs with a windows operating system.
With a standalone DVR you will not be able to perform other functions that you may want; such as internet browsing and word processing.
PC Based DVR
A PC based DVR is a digital video recorder that uses a PC operating system (mainly Windows) and can record your surveillance footage, but it can also act as any normal PC would and operate in that fashion.
Many standard computers can be turned into a PC based DVR, by buying the proper equipment. By getting a DVR card and the software to accompany it you can make your home computer into a DVR capable of recording your security camera footage.
These types of DVRs can be a bit more cost effective; especially if you are using a home PC, and only need to purchase a capture card.
A big downfall for PC based DVRs has to do with their higher chance of breaking down or having buggy issues. The reason for this is because instead of only having to worry about video recording; it now has to deal with all the other programs that are running such as internet browsers, word processors, video games, etc… These additional programs create more strain and complications with the hardware and can cause more problems.
A big setback when it comes to PC based DVRs has to do with storage. If you are running a PC DVR and it is your main personal computer as well; then you will be competing for hard drive space as it records and stores your video.