Optical channel transport unit frames transmission having interleaved parity

A failure monitoring method to be performed by a transmission system composed of a plurality of transmission devices comprising:

• a first transmission device which has a first storage portion for storing first calculation range information indicating either one of a first area including OPTICAL-CHANNEL PAYLOAD UNIT only and a second area at least including an arbitrary byte of OPTICAL CHANNEL TRANSPORT UNIT/OPTICAL DATA UNIT overhead as an area for calculating a bit interleaved parity of 8 bits, a first calculation portion, and an insertion portion;
• and a second transmission device which has a second storage portion for storing second calculation range information indicating the same calculation range as the first calculation range information as an area for calculating a bit interleaved parity of 8 bits, an extraction portion, a second calculation portion, and an error detection portion, the failure monitoring method comprising:
• calculating the bit interleaved parity of 8 bits for an area determined by the first calculation range information among areas of the sending OPTICAL CHANNEL TRANSPORT UNIT frame by virtue of the first calculation portion of the first transmission device;
• inserting the calculation result of the bit interleaved parity of 8 bits from the first calculation portion into the second succeeding OPTICAL CHANNEL TRANSPORT UNIT frame and sending the same by virtue of the insertion portion of the first transmission device;
• extracting the bit interleaved parity of 8 bits from the received OPTICAL CHANNEL TRANSPORT UNIT frame by virtue of the extraction portion of the second transmission device;
• calculating the bit interleaved parity of 8 bits for an area determined by the second calculation range information among areas of the received OPTICAL CHANNEL TRANSPORT UNIT frame by virtue of the second calculation portion of the second transmission device;
• and
• detecting error by comparing the calculation result of the bit interleaved parity of 8 bits from the second calculation portion with the bit interleaved parity of 8 bits extracted by the extraction portion from the second succeeding OPTICAL CHANNEL TRANSPORT UNIT frame after the OPTICAL CHANNEL TRANSPORT UNIT frame for which the calculation result has been obtained by virtue of the error detection portion of the second transmission device.

A transmission device carrying out sending and receiving of OPTICAL CHANNEL TRANSPORT UNIT frames, the transmission device comprising:

• a sending portion;
• and
• a receiving portion,
• wherein the sending portion includes a first storage portion for storing first calculation range information indicating either one of a first area including OPTICAL-CHANNEL PAYLOAD UNIT only and a second area at least including an arbitrary byte of OPTICAL CHANNEL TRANSPORT UNIT/OPTIC DATA UNIT overhead as an area for calculating a bit interleaved parity of 8 bits, a first calculation portion for calculating the bit interleaved parity of 8 bits for an area determined by the first calculation range information among areas of a sending OPTICAL CHANNEL TRANSPORT UNIT frame, and an insertion portion for inserting a calculation result of the bit interleaved parity of 8 bits from the first calculation portion into the sending OPTICAL CHANNEL TRANSPORT UNIT frame;
• and
• wherein the receiving portion includes an extraction portion for extracting the bit interleaved parity of 8 bits from the received OPTICAL CHANNEL TRANSPORT UNIT frame, a second storage portion for storing second calculation range information indicating either one of a first area including OPTICAL-CHANNEL PAYLOAD UNIT only and a second area at least including an arbitrary byte of OPTICAL CHANNEL TRANSPORT UNIT/OPTICAL DATA UNIT overhead as an area for calculating a bit interleaved parity of 8 bits, a second calculation portion for calculating the bit interleaved parity of 8 bits for an area determined by the second calculation range information among areas of the received OPTICAL CHANNEL TRANSPORT UNIT frame, and an error detection portion for detecting error by comparing a calculation result of the bit interleaved parity of 8 bits from the second calculation portion with the bit interleaved parity of 8 bits extracted by the extraction portion.