Patent ID: 8315527
Filing Date: 2012-11-20
Classification: H04B,H04Q

Abstract:
1. A passive optical network system having optical network units (ONU) and an optical line terminal (OLT) that are mutually connected to one another through optical fibers, the ONU comprising: and the OLT comprising: wherein the high-speed OLT unit and the low-speed OLT unit extract a link identifier and a destination address in the upstream signal packet received from the ONU, and when the destination address is not recorded in the high-speed lower band information table or the low-speed downstream band information table, the OLT monitoring controller writes the destination address on a line coincident with the link identifier extracted from the upstream signal packet in the high-speed downstream band information table and/or the low-speed downstream band information table; when the OLT receives a downstream signal packet from a network, the OLT monitoring controller extracts a transmission source address in the downstream signal packet, and checks the transmission source address with a destination address stored in the high-speed downstream band information table or the low-speed downstream band information table under operation, when a destination address coincident with the transmission source address extracted from the downstream signal packet is stored, the OLT monitoring controller sets to the shaper unit ASB and a link identifier set in the address in the high-speed downstream band information table or the low-speed downstream band information table under operation, the shaper unit processes the downstream signal packet, and when an address coincident with the transmission source address extracted from the downstream signal is not stored in the high-speed downstream band information table or the low-speed downstream band information table under operation, the OLT monitoring controller applies to the shaper unit ASB and a link identifier predetermined and set to data whose type is low in priority in the high-speed downstream band information table or the low-speed downstream band information table under operation, the shaper unit processes the downstream signal packet; and in a case where the OLT monitoring controller detects that a trouble occurs in the high-speed OLT unit during operation of the OLT and the ONU at the first transmission speed, when the OLT monitoring controller confirms that no trouble occurs in the low-speed OLT unit and the low-speed ONU unit of the ONU, the OLT transmits a switch notification from the first transmission speed to the second transmission speed to plural ONUs connected to the OLT by using a line of the second transmission speed, and the OLT monitoring controller controls the OLT switch unit to switch the plural ONUs and plural lines connected to the respective ONUs to the low-speed OLT unit side, and changes ASB of the shaper unit so that the low-speed downstream band information table is applied.