When this thread was posted it inspired me to research for a home security system. It is something that I have been wanting to do for some time. I thought I would post what I got, what I paid, and how hard it was to get working.
I really didn't want to spend $1000-$2000 like many of the other systems I had looked at were going for. So I decided that I would use one of my computers as setup and storage and just buy IP cameras. I also had a goal to not pay a monthly fee for this system. I went with a DLink DCS-942L cameras
http://mydlink.dlink.com/products/DCS-942L. I found them for $134 at Amazon. After I bought my first 2 cameras the price went to $142 for the 3rd one. There is free shipping on this item
DLink has a software package that is a free download. It can control up to 32 cameras. It will set the camera up, display video, store video to the hard disk, and replay the video. It took me about 3 hours of time to get the first camera working and that includes a learning curve for the software. The 2nd and 3rd camera were 10 minutes each. The software is very basic but it works. All data from all cameras is stored all the time in H.264 format. You can also use MPEG4. The software allows you to program the record time from each camera based on day of the week. I see no reason to not record all the time so mine is setup to record whenever the computer is on. However, some people may not want what they do when they are at home to be recorded. You can either adjust the time or manually turn off record any time you wish.
The cameras allow you to install a micro SD memory card in them for local recording as well as recording on the computer. The local recording is not fast enough to capture all data. So I use both local and computer recording. It basically stores the data in a cache, then wites it to memory. So it records for about 40 seconds and then doesn't record for about 20 seconds. The cameras can be used in wirelessN or connected to your router with an ethernet cable. They have a AC power cable when you use wireless and get the power over Ethernet when using the wired configuration. The cameras are infrared and record nicely in the dark. There is a motion detector on them and this can be setup to record pictures and/or videos upon motion detection. The setup also allows you to put in an email address and upon motion detection it will send you an email with an attached video or picture. A nice feature if you have a smart phone. There are 4 profiles that can be setup in the camera for snap shots or video. Each one can be configured differently as far as resolution. 640x480 is the top resolution. Not so hot by todays standards, but, this resolution is at the price breakpoint. Higher resolutions than this have a price increase that is exponential. Each one can be setup as to what to do with the data. You can email it, record locally, or send it to an FTP site. The host record feature is separate from the camera setup and it operates separately. I have the host and the camera recordings set up for circular storage. They will record until full and then start recording over the oldest files. The host records for 7 days and the 8 Gbytes SD cards get about 5 days.
I have 3 cameras. One is pointed across the livingroom at the back door. One is pointed across the livingroom to the front door. You can't walk through without both cameras capturing you. The third sits looking out my kitchen window and keeps an eye on my car and the street in front. All cameras record all the time locally and as well as to the computer. I have the 2 livingroom cameras also setup to send me email with a picture when motion is detected. The kitchen window camera does not send email anymore as that was too much email with the cars driving by. I also stopped emailing videos as the picture was good enough. I really just wanted to know when the motion detector went off so the attached picture was just extra.
Altogether the system cost $434. $410 for the cameras and $24 for the micro SD cards. It took less than 4 hours to setup. I have another 10 hours in it messing around learning the software and getting intimate with the features and how to extract videos should I need to provide them to the authorities.
Overall these cameras are an excellent buy for the money. You can find others for less money($75-$100), but give up features. This camera has all of the features of the $500 cameras without the resolution those cameras offer. The DLink sotware also supports many cameras. You could put 1 good one and a few cheap ones on the network if you like.
Two things I don't like: the host computer videos are in a proprietary format. I can't extract a video file and send it off. It must be viewed with the DLink host software. The local camera videos are .avi and can be viewed on any computer. The still pictures are jpeg. So, I have created a CD with the DLink software on it to hand to the police should I ever have a video to show them and the local camera video somehow missed it. I also installed the software on an old laptop that I haven't used in years and may just hand that computer to the police as well.
The second thing is the motion detection. You can set the email up to send 1 email or 6 emails upon motion detection. I used 6 initially during my integration and testing and was just overwhelmed with email. My ISP shut down my account. They thought I had been hacked by spammers. If you set it to 1 email, depending on how fast the person is walking, you may or may not actually get them in the picture. 6 snapshots does get them for sure. I am using 1 now and am making minor adjustments to sensitivity in the detection as well as area of motion detection. I now have the area of detection set to a sliver in the center and that does seem to capture adequately.
DLink has a free website and if you get an account then you can view the live videos remotely. They also have mobile apps for the iphone and droid to do the same. Unfortunately I have a blackberry. However, this latest lack of bb apps has pushed me over the edge. I will be changing soon.
So, for $434, I have a security system that monitors the entire access areas to the home(not the bedrooms) and the front. It has motion detection alarms, sends emails, allows remote viewing, records in 2 places, and is stable - no sotware crashes and no false alarms yet.
I also ran across a software package called Blue Iris. It is $49 and designed to use any flavor of cameras. It has many more features and the host recordings are not proprietary. I am thinking about buying this for the future. But right now, everything works and meets the objective. If someone just bought one camera and placed it appropriately so that it would detect an intruder in the home, like a vast view of the livingroom, you could have a good alarm/security system for $150.