AHD surveillance is an alternative to the IP surveillance. In the case of small systems, it is easier to install and configure. The most important difference between AHD and IP solutions is the method of connecting cameras to the recorder: we do that using dedicated cables. The AHD cameras provide a video quality comparable to the IP cameras, and the basic functionalities of DVRs are similar to those of NVRs.
A major advantage of the AHD solutions (aside from easy installation) is the low cost of the whole system. A similar system based on an NVR and IP cameras costs approx. 40% more than the AHD solution.