Coaxial cable is used for video transmission, cable TV distribution, and certain broadband and security applications. Unlike twisted pair, coax uses a single center conductor surrounded by insulation, a braided or foil shield, and an outer jacket — giving it strong immunity to EMI and consistent impedance across long runs.
In commercial applications, the two most common coax types are RG-6 and RG-59. RG-6 is the standard for CATV distribution, satellite, and cable modem service — it operates at 75 ohms and handles higher frequencies better than RG-59 over longer distances. RG-59 is thinner and more flexible, used in shorter analog CCTV runs, though it has been largely replaced by IP-based camera systems running on Cat5e, Cat6, or fiber.
For new security camera installations in DFW commercial facilities, most projects now use IP cameras over structured cabling rather than analog coax, allowing cameras to draw power via PoE and connect back to network video recorders (NVRs) over the same Cat6 or Cat6A infrastructure used for data.