J0 byte

The J0 byte refers to the numeric value for a SONET section trace to verify the physical connectivity of data links. The J0 byte traces the origin of an STS frame as it travels across a SONET network. The value for the J0 byte parameter is inserted continuously at the source and is checked against the value expected by the receiver. After the data links have been verified, they can be grouped to form a single traffic engineering link.