Independent acknowledgement assembly and its extended mechanisms to enhance TCP performance in OBS networks

This letter investigates how to improve transmission control protocol (TCP) performance over optical burst switching (OBS) networks. Different from previous works, this letter focuses on TCP acknowledgement (ACK) packets. Considering the characteristics of ACK, an independent ACK assembly (IAA) scheme is presented, which assembles ACK into one specific data burst (DBACK) to avoid the disadvantages of the traditional assembly mechanism and improve TCP throughput. Based on IAA, three extended mechanisms, i.e., IAA with DBACK cloning (IAA-DC), IAA with DBACK retransmission (IAA-DR) and IAA with DBACK deflection routing (IAA-DDR) are proposed respectively. Simulation results show that these new mechanisms can further improve TCP throughput performance.