Patent ID: 8730976

Claim:
A method comprising: detecting an identifier change from an old identifier to a new identifier; updating a value of a flag, in response to the detecting, wherein the updated value of the flag indicates that the old identifier should be included in one or more PAgP PDUs; sending a Port Aggregation Protocol (PAgP) protocol data unit (PDU), wherein the PAgP PDU comprises the new identifier and the old identifier, the new identifier identifies a network device subsequent to the identifier change, the new identifier is a Media Access Control (MAC) address, the PAgP PDU comprises an “old device identifier” field, the “old device identifier” field of the PAgP PDU comprises the old identifier, and the old identifier identifies the network device prior to the identifier change; and sending a second PAgP PDU, wherein the second PAgP PDU does not include the “old device identifier” field, and the sending the second PAgP PDU occurs prior to the detecting; receiving a third PAgP PDU subsequent to the updating the value of the flag, and preventing an interface from being removed from an aggregated interface, in response to receiving the third PAgP PDU, wherein the third PAgP PDU comprises the old identifier, and the third PAgP PDU is received by the interface.