How do I implement a simple video surveillance system in C#?

I have just one idea.

Such questions are usual and they manifest certain misconception driven by the predominant use of client-server model. This "most-used" model assumes that there should be one big server and many clients. Being very usual for, say, financial application, this model is quite inefficient in many other cases, including the cases of diagnostics, surveillance and a lot more. In such cases, you should have just the opposite pictures: many small simple services and just one or very few clients.

Just think about it: as soon as you have a computer immediately connected with some hardware (say, one or more webcams), this very computer should play the role of the streaming service. As you want to work via the Web (I'm not sure this is a best option, because surveillance application can be considered as mission-critical, but Web technologies are not designed for mission-critical application), you have two options: it can be a pure streaming service streaming video to a connected (subscribed) client serving as an intermediate tier, or each of such devices should play a role of the small HTTP server. Here, you should understand that a minimal HTTP server would create a tiny overhead in comparison with streaming software. Then a client would be either a big network client connecting to several services at a time and showing them all together, or just a browser.

However, I would advise to exclude the Web from equation and work with pure streaming using just the streaming protocols. This way, you can gain dependability of the whole system much closer to mission-critical requirements.

—SA