Relay device, relay method, and optical communication system which uses relay device

Abstract

A relay device includes a first transmitting and receiving unit connected to a PON line on the upper-level side and performing mutual conversion between optical and electrical signals; a second transmitting and receiving unit connected to a PON line on the lower-level side and performing mutual conversion between optical and electrical signals; a relay processing unit relaying a downstream frame received by the first unit to the second unit, and relays an upstream frame received by the second unit to the first unit; and a control unit. The control unit follows upstream multiple access control performed by a station side device, for transmission of the upstream frame to be transmitted by the first unit to the station side device, and independently performs upstream multiple access control for reception of the upstream frame received by the second unit from a home side device.

1 - 19 . (canceled) 
     
     
         20 : A relay device for cascading upper and lower networks of P2MP topology that adopts MPCP, the relay device comprising:
 a first transmitting and receiving unit connected to the upper network,   a second transmitting and receiving unit connected to the lower network,   LLID solution means that associates a logical link of the upper network with a logical link of the lower network so that there is one-to-one correspondence between the logical links, and   a control unit that is configured to:   reconstruct a downstream OAM loopback frame generated by a station side device in the upper network from a received signal of the first transmitting and receiving unit, and then relay the downstream OAM loopback frame to the second transmitting and receiving unit, and   reconstruct an upstream OAM loopback frame generated by a home side device in the lower network from a received signal of the second transmitting and receiving unit, and then relay the upstream OAM loopback frame to the first transmitting and receiving unit.   
     
     
         21 : A relay device according to the  claim 20 , wherein
 the second transmitting and receiving unit runs at an upstream transmission rate different from an upstream transmission rate of the first transmitting and receiving unit.   
     
     
         22 : A relay device according to the  claim 20 , wherein
 the second transmitting and receiving unit runs at a downstream transmission rate different from a downstream transmission rate of the first transmitting and receiving unit.   
     
     
         23 : A relay method performed by a relay device for cascading upper and lower networks of P2MP topology that adopts MPCP, and
 a logical link of the upper network and a logical link of the lower network are associated with each other so that there is one-to-one correspondence between the logical links; the method comprising the steps of:   reconstructing a downstream OAM loopback frame generated by a station side device in the upper network from a received signal from the upper network, and then relaying the downstream OAM loopback frame to the lower network, and   reconstructing an upstream OAM loopback frame generated by a home side device in the lower network from a received signal from the lower network, and then relaying the upstream OAM loopback frame to the upper network.   
     
     
         24 : An OAM loopback testing method performed in a communication system, the system comprising
 a station side device provided in a upper network of P2MP topology that adopts MPCP,   a home side device provided in a lower network of P2MP topology that adopts MPCP, and   a relay device cascading the upper and lower networks,   a logical link of the upper network and a logical link of the lower network are associated with each other so that there is one-to-one correspondence between the logical links; the method comprising the steps of:   relaying, by the relay device, a loopback set request from the station side device to the home side device, and then relaying, by the relay device, a loopback set response from the home side device to the station device, and   relaying, by the relay device, a loopback test frame from the station side device to the home side device, and then relaying, by the relay device, a loopback test frame from the home side device to the station device.   
     
     
         25 : A relay device for cascading upper and lower networks of P2MP topology that adopts MPCP, the relay device comprising:
 a first transmitting and receiving unit connected to the upper network,   a second transmitting and receiving unit connected to the lower network,   LLID solution means that associates a logical link of the upper network with logical links of the lower network so that there is one-to-many correspondence between the logical links, and   a control unit that is configured to:   control the first transmitting and receiving unit so as to transmit a received OAM loopback frame to a station side device by return, when the first transmitting and receiving unit receives the downstream OAM loopback frame generated by the station side device in the upper network.   
     
     
         26 : A relay method being performed by a relay device for cascading upper and lower networks of P2MP topology that adopts MPCP, and
 a logical link of the upper network and logical links of the lower network are associated with each other so that there is one-to-many correspondence between the logical links; the method comprising the steps of:   receiving a downstream OAM loopback frame generated by a station side device in the upper network, and   transmitting the received OAM loopback frame to the station side device in the upper network by return.