Network cameras are unlike their webcam siblings in that they are self-contained, IP-addressable units that can operate without an attached PC.  Generally speaking, they have a built-in web server and an FTP client.  They often support telnet and DDNS (Dynamic DNS) as well.  Most also have a small amount of memory.  They are, basically, small computers with a wired or wireless Ethernet connection and a camera.  Oh yeah, as you might expect, they are also a lot more expensive than web cameras.

While I am certainly no expert, I have installed 5 network cameras for personal use to date and have learned enough to know that I’d do it differently if I were to start all over again.  Hopefully, my experience may help others get to their ideal solution faster.

The feature sets of these cameras are difficult to compare on an apples-to-apples basis.  There are cameras made for homes and small businesses and there are cameras made for industrial use and video surveillance.  Knowing what’s important to you before diving in will save you a lot of time and, probably, money.  For example, if you just want to see if a moving van is parked in front of your house being loaded with all your worldly possessions while you’re away, you probably don’t need a camera with a large sensor, high resolution and a lightning fast frame rate.  If, however, your camera is looking out at Old Faithful in Yosemite, you probably want the best video at the highest resolution possible so that you get the most breathtaking pictures possible.  You get the idea.

With that here are the basics . . .

At the remote site, where the camera is located, you’re going to need:

• Power – we’re talkin’ 120V 60Hz type power (in the US, at least) – these cameras can’t run off the measly power from a USB port
• A computer or a good router that lets you play with port mapping
• A weatherproof enclosure for the camera if it’s going to be exposed to the elements and it doesn’t come with one
• A wireless access point (can be your router, of course) if you’re going wireless
• A backup power source (UPS, etc – completely optional, but some of these cameras don’t handle hard reboots very well)

Also, at some central location (which because of the wonders on the Internet, doesn’t even have to be on the same continent as your camera), you’ll need a computer or web server where you’ll view the output of the camera or consolidate its images and/or video feeds.

If any of these things seems foreign to you, now would be a good time to hire someone to set your system up, reassess your desire to take on this project, or allocate a lot more time to the project than you ever expected (see The Bower Factor).

Now, how do you choose which camera to use.  Here are the basic questions about functionality you need to ask yourself, IMO . . .

• Technical details – sensor size, frame rate, resolution – the best cameras have larger sensors (1/2″) with high resolutions (3MP) and really fast frame rates (250 frames/sec).  If your pictures/video are going to be evidence at a trial or your video is going to be used by National Geographic, then you want to maximize all of these.  Smaller sensors (1/4″) shooting sub-one megapixel images at one frame/sec are often fine for what you need and cost a lot less.
• Do you need audio with your video?  Many cameras have either a built-in microphone, or a connector to control one.
• Is the camera for outdoor use?  If so, get a camera made for it, not one that needs to be put in a case.  The outdoor enclosure will add size, complexity, weight, etc.
• How are you going to power it?  If it’s hard to get to or far from power, you need it to use POE (Power Over Ethernet – where power is run through you CAT5/6 cable).  Most cameras do not have this feature.  Some cameras have custom cables that bundle separate power and communication cables.  Not as elegant and more expensive, but work just as well.
• What do you want out of the camera, stills or video?  This is a tough one.  Most cameras won’t let you query them for a still image without using their own software (you can almost always get a dynamic image from any camera if you use the manufacturers application or access the web server inside the camera from a browser).  This prevents you from putting the image up on your own site.  Most cameras do, however, have a trigger for timed FTP uploads of images so you can have an image sent to your computer/server at specified intervals.  Video handling can be even tougher and many manufacturers require that you use their custom application.  If putting video in your custom application or web site is what you want, make sure that the camera lets you do it.
• Do you want motion triggering (a picture or video is taken when motion is detected)?  Not all cameras have this and it’s useless for outdoors (if there is almost constant motion in the background – think trees, animals, people).  This feature is great for security purposes where you’re actually looking for motion.
• Do you want pan and zoom?  If you want to be actively involved in what the camera is pointed at and it changes, you want this feature.  Most often, you need to use the camera’s web page or the manufacturers custom application to control it.  These features also add to the complexity and price.  But, if you need it, you need it.  Make sure you look up user reviews about the particular pan and zoom camera you’re looking at.  There are loads of cameras that fail with bad motors.
• Do you need wireless?  Before just choosing to go this way, think about the bandwidth you’ll need to feed live video (yes, it is highly compressed).  How far are you from your access point?  How good is the signal?  You know the deal here.
• Do you need to see what’s going on without much light?  All cameras struggle with low light.  Some handle it better than others.  If you’re buying cheap, make sure you get a camera that switches over to black and white images as the light gets weak instead of just continuing to struggle with color.  For comparison purposes, check out the lux (light sensitivity) of the camera.  The lower the number, the better it’s supposed to handle low-light conditions.
• How much do you want to spend?  These cameras can get expensive fast.  You’ll need to balance your desire for the features in this list with the size of your wallet.

In terms of specific manufacturers, I can’t claim any particular expertise.  I’ve tried cameras from a variety of manufacturers and I can’t say that any one has stood out.  In fact, I could list fairly significant problems with each camera I’ve tried.  My biggest issue has been that I only began to understand the features and what I actually needed from the cameras as I began to put them in place and get them working. Thus, this list.  Hopefully, it’ll help you figure out which cameras meet your needs right out of the box instead of having to buy-and-try like I did.