An application program may be executed through an Internet protocol (IP) address linkage in an image forming apparatus supporting a peer-to-peer connection. The application program may be executed by performing a method which includes connecting the image forming apparatus to a wireless device through a wireless local area network, driving a soft access point (AP) module of the image forming apparatus so that the image forming apparatus functions as an AP, driving a dynamic host configuration protocol server of the image forming apparatus to allocate a dynamic IP address to the connected wireless device, and linking the dynamic IP address allocated to the wireless device with a static IP address that is preset with respect to the wireless device.