Patent ID: 7869687

Claim:
An optical network unit (ONU) of a passive optical network system having an optical line terminal (OLT) and a plurality of optical network units connected to terminal users and the optical line terminal, the optical network unit comprising: a memory; a photoelectric conversion unit which photoelectrically converts signals from the terminal user and the optical line terminal; and a frame processing unit having a monitoring unit which monitors a channel request transmitted from the terminal user and an optical layer filter which selectively transmits, to the terminal user, a frame signal transmitted through the optical line terminal from an IPTV server, the memory being configured to hold a channel list to record a correspondence between channel information and optical transmission information of a channel of the passive optical network (PON), the optical network unit being configured to monitor channel information included in a multicast message received from the optical line terminal, and if the channel information is not included in the channel list held in the memory, update the channel list to add a correspondence relation between the channel information and optical transmission information included in the received multicast message.