Methods, devices, communication systems, and computer program products for discarding a duplicate protocol data unit associated with a data transmission via a first signaling radio bearer or a second signaling radio bearer are described. A method for discarding a duplicate protocol data unit associated with a data transmission via a first signaling radio bearer or a second signaling radio bearer is performed by a device. The method includes receiving a protocol data unit, verifying an integrity of the received protocol data unit in an integrity verification procedure, determining whether the successfully integrity verified protocol data unit is a duplicate protocol data unit, and discarding the protocol data unit based on determining that the successfully integrity verified protocol data unit is a duplicate protocol data unit.