scope:

The present document specifies the Packet Forwarding Control Protocol (PFCP) used on the interface between the control plane and the user plane function.

PFCP shall be used over:

-the Sxa, Sxb, Sxc and the combined Sxa/Sxb reference points specified in 3GPP TS 23.214 [2].

- the Sxa' and Sxb' reference points specified in 3GPP TS 33.107 [20]. In the rest of this specification, no difference is made between Sxa and Sxa', or between Sxb and Sxb'. The Sxa' and Sxb' reference points reuse the protocol specified for the Sxa and Sxb reference points, but comply in addition with the security requirements specified in clause 8 of 3GPP 33.107 [20].

the N4 interface specified in 3GPP TS 23.501 [28] and 3GPP TS 23.502 [29].

In this specification the term CP function applies to control plane nodes such as SGW-C, PGW-C, TDF-C and SMF.

In this specification the term UP function applies to control plane nodes such as SGW-U, PGW-U, TDF-U and UPF.

The prefix PFCP in message and procedure names is used to indicate that messages and procedures are common and used on Sx and N4 reference point. A PFCP session refers to both Sx and/or N4 sessions. PFCP association are describing procedures to establish associations between EPC nodes (SGW-C/PGW-C/TDF-C and SGW-U/PGWU/TDF-U) and also between 5G nodes (SMF and UPF).

In the related stage 2 specifications the prefix Sx and N4 is used for these common procedures realised by PFCP

Clauses or paragraphs that only apply to EPC or 5GC are indicated by the label "for EPC" or "for 5GC".