Patent ID: 7412165

Claim:
A system comprising: a testing device configured to be connected to at least one network node of an optical communications network having a data communication channel, the testing device being configured to receive signals from the data communication channel of the network node; and a data communication channel loop back plug coupled to the testing device for returning to the network node any signals within the data communication channel received at the testing device, the data communication channel loop back plug comprising a plurality of pins, at least one of the pins being shorted to at least one other of the pins to return to the network node any signals within the data communication channel received at the testing device, wherein the data communication channel loop back plug comprises: i) a 15 pin connector, and wherein pin 2 of the data communication channel loop back plug is shorted to pin 14 , pin 4 is shorted to pin 12 , pin 5 is shorted to pin 6 , and pin 8 is shorted to pin 10 , or ii) a 37 pin connector, and wherein pin 4 of the data communication channel loop back plug is shorted to pin 6 , pin 8 is shorted to pin 17 , pin 22 is shorted to pin 24 , and pin 26 is shorted to pin 35 .