METHOD AND SYSTEM FOR LOSS MITIGATION DURING DEVICE TO DEVICE COMMUNICATION MODE SWITCHING

A method for managing data packets (IP PDUtx, PDCP PDUtx, RLC PDUtx, MAC PDUtx) transmitted by a first user equipment (105tx) to be received by a second user equipment (105rx) is proposed. The first user equipment (105tx) is arranged for communicating with the second user equipment (105rx) in a direct mode by directly connecting to the second user equipment (105rx) or in an infrastructure mode by connecting to the second user equipment (105rx) through a radio transceiver station (110) of a radio network. The first user equipment (105tx) is configured for generating data packets (IP PDUtx) at an Internet Protocol layer (205) of the protocol stack to be transmitted; forwarding each data packet (IP PDUtx) to a lower protocol layer (210) of the protocol stack in order to be sent to the second user equipment in direct mode or in infrastructure mode, providing at least one buffer protocol entity (405) below the Internet Protocol layer (205). The at least one buffer protocol entity (405) is arranged for storing a copy of each data packet (IP PDUtx) forwarded from the Internet Protocol layer (205) to the lower protocol layer; removing the copy of a data packet (IP PDUtx) stored in the buffer protocol entity (405) upon acknowledge of the receipt of the corresponding data packet at the second user equipment, and in case the first user equipment switches from communicating with the second user equipment (105rx) in the direct mode to the infrastructure mode or, vice versa, from the infrastructure mode to the direct mode, forwarding the copy of each data packet (IP PDUtx) comprised in the buffer protocol entity (405) to the lower protocol layer of the protocol stack in order to be sent to the second user equipment in infrastructure mode or in direct mode, respectively.