If the Use_DEI is set to true(1) for the Port then the drop_eligible parameter is encoded in the DEI of transmitted frames, and the drop_eligible parameter shall be true(1) for a received frame if the DEI is set in the VLAN tag or the Priority Code Point Decoding Table indicates drop_eligible True for the received PCP value. If the Use_DEI parameter is false(2), the DEI shall be transmitted as zero and ignored on receipt. The default value of the Use_DEI parameter is false(2).