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Basically it comes down to transmission and encoding.

 

The goal is to have stored digital video.

The cameras already are digital.

 

You can have a digital camera send an analog signal that conforms to the NTSC 3 standards set in the 80s. This standard is why all analog cameras work equally well with all analog recorders. In this case the DVR is doing the encoding to whatever formats it supports, MPEG4, H.264... These formats are pretty darn effiecient storage wise and the "You get what you paid for." comes in the quality of the compression techniques and settings utilized. DVRs use either a hardware encoder chip, the CPU of the host computer or a combination of, to compress the video.

 

You can now have a digital camera send a combination of digital and analog feeds. There really is no set standards for IP based cameras. IP based cameras do not by themselves adhere to the NTSC standard, as such they do not all play nicely together. IP based cameras are not limited by NTSC standards is more like it. In most IP based "NVR"s the compression is done in the camera, utilizing an encoder chip. The NVR basically serves as storage for the video and an integrated user interface, usually any features live here too.

 

Analog>Upsides

 

Total compatiblity

Readily available

Cheap

Well established technology

Storage friendly

 

Analog>Downsides

 

480i MAX resolution

29.97fps MAX

 

 

IP>Upsides

 

Frame size limited by modern networking, almost limitless

Frame rate also limited by modern networking

Many have multiple formats and multi streaming

Distance is not nearly the issue anymore, 1 NVR can monitor several cameras states apart

They can be cost effective

 

IP>Downsides

 

Camera encoding kinda sucks right now, compared to quality DVRs anyway

Most NVRs I have seen do not transcode the video for storage, as such the highly compatible MJPEG is used. This is a storage beast!!!

Cost

Alot of toy like IP cameras that have sub analog performace

Few quality cameras available, most seem based on cheap analog systems

 

 

Wireless comes into play as IP cameras give you some privacy.

IP cameras use existing networking gear, so it's wifi now.

 

I have little to no wireless experience so hopefully WirelessEye will chime in.

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Can anybody direct us to good info regarding the benefits of IP over analog, especially with regard to wireless applications. Thanks much!

 

better choose analog...because no need high tech device, no need switch..no need configure....

choose analog bacause pricing....

so if u want save your money...go to analog cctv

 

 

[edit by mod - link removed for obvious reasons - rk]

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analog "wireless" works ok but encryption is really expensive -unless you want it seen.

 

You can digitize it of course.

 

Digital [iP] is a easy to encrypt and free also a mature system. you dont really need a switch you could use a POE injector .anyway you can get a switch for $50 they are cheap.

 

IP is is new in the security world but 20 years old in reality

 

I would go for IP its more future proof and flexible and you can hook it to your existing network.

 

analog for cheapness for sure

 

my 2c

z

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Network Video Servers if you need wireless, as then you dont need a seperate TX and RX for each camera, as you do with so called "analog".

 

The thing is, DVRs have had integrated IP capability for many years now.

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anyone people know about DVTEL??

dvtel have a encoder and decoder to convert from analog camera to Digital, means convert analog to IP

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DVTEL is not the only company making encoders and decoders. Pelco has the PelcoNet series, Bosch has the VIPX line and Optelecom-nkf makes a full line. There are others too.

 

Keep in mind that if you convert analog to IP, your video is limited to analog resolution, whereas IP cameras can be megapixel.

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IP Cameras relied on the network to transmit and store images.

Over LAN, it'll consume your bandwith for image tranmission tramission and storage. When you have multiple cameras, it'll slow down your network. It's more advisable to have dedicated switch for your ip cameras and nvr, and then link it out to your main network rather than put them all together. But that'll require you to have dedicated network cable wiring from the point to your server room, instead of just using a switch to split off an existing network point. So when doing enterprise level installation, basically your'll really have to do recabling again, unless the company have a lot of spare network cable and capacity.

Over Internet, it really depends on what kind of internet bandwith you have.

Normally, for internet tranmissoin, you will not have a upstream bandwith.

Image storage is only as good as your image tramission.

i.e. if you got a slow network, your frame transmission would be slow as well, and recording would only be as good as the frame tranmistted. e.g. if you can only get 2-3FPS for tranmission, recording can only be done at that fps, even if your nvr/ip cam support 30fps. And internet, as we know, is shared infrastructured. Bandwith is never guaranteed, unless you are talking abt running a dedicated line from 1 office to another (that's not internet). So if there's ever a guaranteed speed, so relying on that for recording is risky. if there's a disconnection, there'll not be a recording. If there's a heavy traffic or slow down in traffic, you'll get a bad recording.

IMHO, that's damm risky. I rather do recording locally as well.

Normally what i recommend.

1. If you just want to remote monitor (and have only 1 or 2 cam), go for IP Camera.

2. If you got a lot of camera you want to monitor, go for DVR solution, cheaper total cost.

3. If you really need recording, forget abt IP camera.

As i always said.... what's good of remote monitoring camera if you can't be sitting in front of your comp to monitor 24 x 7 ? Anything happens while you are not watching is as good as not having a system in place. I'd reommend recording w/o remote monitoring rather then just monitoring w/o recording. Even if u see, no recording, no proof.

Above pts are taking into consideration that budget is of a concern. Of course, there are high end equipments that can slow some of the prob in the IP cam and NVR. Then again, most solution with Standalone NVR are already priced on the higher side.

That's my 2 cents worth of opion for ip cameras.

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Ip cameras lend themselves toward a wireless infrastructure much better. Wireless analog pictures are very unstable at the price range most CCTV people are willing to pay. Ip cameras are TCP/IP datastreams and can be sent using everything from a simple Linksys AP to a complicated mesh network with no difference in set-up of performance in most cases. The wireless links now are so much better than 5 years ago, I have seen 7mile links work fine on first setup. Mesh network loading can be more difficult as due to a high bitrate of data throuput, should one mesh node drop the packets must be routed though the mesh and this can cause issue if you havent done your homework.

 

Hope this helps you.

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