Study on system enabler for service function chaining
The Technical Report studies and performs evaluations of potential architecture enhancements to enhance the support of service function chaining in the 5G Core network (5GC). Specifically, two objectives are included:
WT#2: Investigate whether traffic steering policy is sufficient to support SA WG1 requirements in TS 22.101 [5], TS 22.261 [6] and TS 22.115 [7], study whether and how to define Service Function Chaining (SFC) policies, and investigate solutions and procedures for the 5G network with SFC capabilities to identify/detect/classify user plane traffic and steer the traffic to a chain of ordered service functions for SFC processing in non-roaming and home routed roaming scenarios.
WT#3: Depending on the outcome of WT#2, specify possible enhancement to northbound APIs for allowing an AF to request network capability exposure functionalities, e.g. request a service function chain for a certain traffic flow, etc. based on service level agreement with the third party.
NOTE 1: This study considers only traffic handled over N6 by PSA UPF(s) in 5G network.
NOTE 2: The definition of terms in RFC 7665 [8] may be re-used when applicable. The study targets the use of traffic steering concept, e.g. defined by 3GPP (FMSS) and SFC mechanisms defined in IETF when applicable. Especially the study aims at reusing user plane mechanisms (e.g. VXLAN, NSH, GENEVE, GRE, VLAN, etc.) defined at IETF to support SFC, as applicable.
NOTE 3: The study for SFC will ensure that existing (per 3GPP Rel-17) deployments flexibility can be preserved in deployments of SFC in 5G network.
NOTE 4: The study assumes a Home Routed roaming PDU Session does not have an offloading point in a VPLMN.