A digital broadcasting system and a data processing method are disclosed. A receiving system of the digital broadcasting system includes a baseband processor, a management processor, and a presentation processor. The baseband processor receives broadcast signals including mobile service data and main service data. Herein, the mobile service data may configure a RS frame, which includes mobile service data and table information describing channel configuration information and IP access information of an ensemble level corresponding to the RS frame. The table information is encapsulated to a UDP/IP header. The management processor processes table information from the RS frame to acquire channel configuration information and IP access information of an ensemble level, and accesses mobile service data requested to be received from the RS frame, based upon the acquired information. The presentation processor decodes the accessed mobile service data and outputs the decoded data to a display screen and/or a speaker.