Broadcast signal receiving apparatus and broadcast signal receiving method

A method of receiving a broadcast signal, the method comprising:

• receiving the broadcast signal;
• processing the broadcast signal to output link layer packets;
• decapsulating the link layer packets to output data packets comprising service data for a broadcast service, wherein the data packets are included in payloads of the link layer packets;
• decoding the data packets to output the service data for the broadcast service;
• and
• presenting the broadcast service by using the service data,
• wherein each of the link layer packets further includes a header including packet type information for identifying a packet type of data included in a payload of a corresponding link layer packet and header extension flag information for identifying whether an optional header is present, and
• wherein the header further includes the optional header having an extension type field, an extension length field and extension header information for the service data, the extension type field identifying a type of the optional header and the extension length field providing information about a length of the extension header information in response to the header extension flag information identifying that the optional header is present.

An apparatus for transmitting a broadcast signal, the apparatus comprising:

• a first processor configured to generate data packets comprising service data for a broadcast service;
• a second processor configured to generate link layer packets using the data packets,
• wherein the data packets are included in payloads of the link layer packets, wherein each of the link layer packets further includes a header, and
• wherein the header includes packet type information for identifying a packet type of data included in a payload of a corresponding link layer packet and header extension flag information for identifying whether an optional header is present;
• a third processor configured to generate the broadcast signal using the link layer packets;
• and
• a fourth processor configured to transmit the broadcast signal,
• wherein, when the header further includes the optional header having an extension type field, an extension length field and extension header information for the service data, the extension type field identifying a type of the optional header and the extension length field providing information about a length of the extension header information, the header extension flag information identifies that the optional header is present.

A method for transmitting a broadcast signal, the method comprising:

• generating data packets comprising service data for a broadcast service;
• generating link layer packets using the data packets, wherein the data packets are included in payloads of the link layer packets,
• wherein each of the link layer packets further includes a header, and
• wherein the header includes packet type information for identifying a packet type of data included in a payload of a corresponding link layer packet and header extension flag information for identifying whether an optional header is present;
• generating the broadcast signal using the link layer packets;
• and
• transmitting the broadcast signal,
• wherein, when the header further includes the optional header having an extension type field, an extension length field and extension header information for the service data, the extension type field identifying a type of the optional header and the extension length field providing information about a length of the extension header information, the header extension flag information identifies that the optional header is present.