Data Duplication for High Reliability: A Protocol-Level Simulation Assessment

Among the key 5G targets is to offer “ultrareliable” communication services with packet loss rates not exceeding 10
^-5
. It is widely acknowledged that this objective can be achieved only in multi-cellular setups with a special use of multi-connectivity, known as data duplication. This paper examines the use of data duplication at layer 2, i.e., at the Packet Data Convergence Protocol (PDCP) layer of the protocol stack. Unlike many alternative schemes, it does not rely on detailed channel state information or coordination in layer 1, but relies on feedback and coordination at layer 2 only, including a new level of packet acknowledgments. Using system-level simulations the efficiency of the proposed scheme in a real-world environment is illustrated. Besides packet loss rate, the system performance against throughput and delay at the application layer is assessed.