In many surveillance applications you would wish to place a camera to cover a large area. To be able to turn your camera around and zoom in to
focus your attention is a powerful benefit. With ACTi’s KCM series auto focus zoom cameras, you get an unparalleled video quality and efficientzooming at high megapixel solution. A Pan-Tilt Scanner (Pan-Tilt Head) will help you turn the camera around and aim at wherever you desire.

It is also good to know that the zoom cameras KCM-5211E and KCM-5311E come with built-in IR LED. While traditional speed dome cameras do not have IR LED because of possible IR light reflection risk due to dome cover design, the IR LED supported box cameras together with Pan-Tilt scanner can see in any direction even in total darkness!

How it works
Many PTZ scanners are controlled by special analog protocols mostly based on RS-485 interface. The most widely used protocol is Pelco-D. ACTi Autofocus Zoom cameras will translate IP based PTZ commands into Pelco-D commands and send it to telemetry receivers, which can understand the Pelco-D commands and convert it again into motor movement signals for Pan-Tilt heads attached to the camera. This allows the Zoom cameras to do pan and tilt in real time. As there are many Pan-Tilt scanners available in the market, the Pan-Tilt performance will depend upon the PT scanner unit connected to the Zoom camera.

If you use a control panel with joystick for PTZ control that supports Pelco D protocol, you can just wire it to a video decoder, which will convert the PTZ controls into IP format for Zoom cameras.

In such cases, one of the practical networking solutions is to use DSL modem on camera site and let the camera obtain the dynamic IP address from the Internet Service Provider through the DSL modem using PPPoE connection, which is much more cost-effective than applying for static IP address.

However, there is one drawback in this solution – in order to do the remote surveillance from the Control Center, the NVR Server in the Control Center has to know the address of the IP camera at all times in order to get the video stream from the camera. If the camera’s network connection has been reset for any reason, the camera will get a new IP address through DSL Modem, which may be different from the previous one. NVR will not know about this change, and the connection between the camera and NVR will fail.

The good news is – there exists a solution that makes sure the NVR can find the camera even if the camera IP changes frequently. ACTi cameras support Dynamic DNS service that allows frequently changing IP be mapped to a certain unchangeable domain name. The mapping database and its updating engine are hosted in one of the Dynamic DNS servers, most of which offer basic services for free, such as www.dyndns.org.

Every time the IP camera gets an IP that is different from previous one, it notifies the public DDNS Service about the change. The DDNS Service updates its database immediately, mapping the assigned domain name (for example tcm7411.dyndns.org) to the new IP address.
In NVR settings, only the domain name (tcm7411.dyndns.org) is used to identify the camera.

Every time when NVR needs to connect to the camera, it asks from DDNS Service what the current camera’s IP is. The DDNS Service instantly responds to NVR and tells it the camera’s IP. Now NVR will use the IP of the camera to connect to the camera and the video stream from the camera to NVR can be initiated.

As a result, NVR can always find the IP camera regardless of frequently changing IP address of the camera. Since there are so many public DDNS Services available for free, the PPPoE-based connection is really a good and low-cost solution for single-camera sites.

Although the theoretical explanation might be clear by now, you might still want to know the step-by-step procedure of how to set up the PPPoE together with DDNS support.