OsmoUPF¶

Osmocom User Plane Function; manages a GTP user plane controlled via 3GPP PFCP (Packet Forwarding Control Protocol).

This is not a fully-featured UPF implementing every obscure option ever specified by 3GPP. Rather, it is a simple implementation, covering only the basics.

Its design goal was to try to see what kind of performance we can get from an unmodified mainline Linux kernel, without adding new kernel modules or even going down the rabbit hole of DPDK, VPF or other non-standard (from the Linux kernel perspective) subsystems.

It currently supports mainly two use cases:

• encapsulation/decapsulation (like it would happen on a GGSN / PGW element)
  • this is implemented using the standard linux-kernel-gtp-u module
• tunnel mapping (like it would happen on a SGSN / SGW element
  • this is implemented using the standard linux kernel packet filter nftables