Packet Level Resilience for the User Plane in 5G Networks

The growing demands of ultra-reliable and lowlatency communication (URLLC) in 5G networks necessitate enhanced resilience mechanisms to address user plane failures caused by outages, hardware defects, or software bugs. An important aspect for achieving ultra-reliable communication is the redundant transmission of packets, as also highlighted in 3GPP Release 18. This paper explores leveraging the Packet Replication, Elimination, and Ordering Function (PREOF) to achieve 1+1 path protection within private 5G environments. By extending existing 5G components with mechanisms for packet level redundancy and offloading the reordering mechanism to external servers, the proposed approach ensures minimal packet loss in case of a failure. A conceptual integration of redundant paths and programmable elements is presented, with considerations for deployment in existing 5G infrastructures and the trade-offs of latency versus enhanced traffic engineering. Future work aims to evaluate practical implementations using an open source 5G core, P4-based hardware and offloading technologies like DPDK and eBPF.