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ADSL for CCTV (what are the limitations)

ADSL modem for CCTV

It is quite common calls for technical support from CCTV system integrator and distributors, the common complaint is the speed of the CCTV video via the Internet. But is really the problem on the cameras ?

In most cases the problem is in the Internet link or in the lack of correct configuration of the equipment (router)

For the ADSL tecnology, the download speed is faster than the Upload speed

Download
Upload

But what is the reality behind an ADSL link that does not allow for good video streaming from security cameras? There are several factors listed below:

1. ADSL Asynchronous Link

The "A" on ADSL means asynchronous, this means that the download speed (from the Internet to the user) and the Upload (from the user to the Internet) are different and the upload speed is much lower than the download speed, in most cases it reaches 1/8. Guess which one is used by the camera to send the videos to the Internet? That's right, the upload speed.

That means that when we buy a link of 2 Mbps this is the download speed and we will only have about 250 Kbps of upload

2. Average speed

The Internet carrier does not provide 100% of the speed, if you read the small letters of the contract will find that there is a minimum percentage that they must comply. All depends on you country and carrier, but in most countries the average of guaranteed download is 10% of the total link speed.

3. Link sharing

It is common in homes and businesses the ADSL link to be shared by several users, so if someone is browsing Facebook to post images, or is sending emails to friends, using P2P software, etc that will impact on the amount of bandwidth available for the  camera to transmit the  video .

A modern CCTV camera does an excellent job with image generation and transmission especially using the H.264 codec that delivers an excellent image using little bandwidth, it is also possible to create different profiles of transmission in the camera and which one can have a rate transmission to suit Internet traffic. But you need to know which link your really working with. In most cases the problem is not in the camera.

==> I highly recommend you to learn more about bandwidth and storage, so please read the article: Bandwidth and storage for CCTV.

Find out the best Internet option for you be happy!

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