A wireless adapter and method for providing a wireless connection to at least one wired security device includes at least one combined data/power physical port to which the wired security device connects. A power supply module receives power from an external power source and a power injector provides power to the combined data/power physical port to thereby power the wired security device. In this way, the wireless adapter supplies both power and data connection at the same physical port/jack of the wired security devices, such as IP security cameras, via an interface cable from the wireless adapter. This configuration has advantages in lowering the manufacturing costs of the cameras and reducing installation costs. Furthermore, the same standard camera can be used for both standard wired connections and wireless connections.