Receive Side Scaling Analysis of eXpress Data Path Extensions for 5G User Plane Functions

In 5th Generation networks, the User Plane Function forwards the data of the different users in the Radio Access Networks to the destination networks. To improve the throughput of this component, we used the software acceleration technique eXpress Data Path (XDP) in previous work to shift the processing of GTP-U tunnel connections in the kernel. The developed solution for an XDP Receive Side Scaling (RSS) in the uplink direction distributes the encapsulated traffic across the CPUs, but the measured throughput was significantly lower than in the downlink direction. In this work, we investigate the impact of multiple connections in the downlink direction with RSS by Network Interface Card (NIC). For leveraging this NIC feature in the uplink direction, we propose a sender-side source port variation in combination with XDP enhancements. In RFC2544 frame loss tests, we evaluate the performance with an increasing number of GTP-U tunnels.