Section: 4.26 Network Function/NF Service Context Transfer Procedures 4.26.1 General
Content: Network Function/NF Service Context Transfer Procedures allow transfer of Service Context of a NF/NF Service from a Source NF/NF Service Instance to the Target NF/NF Service Instance, e.g. before the Source NF/NF Service can gracefully close its NF/NF Service. If SMF sets are deployed this applies from an SMF instance within an SMF set to an SMF instance of another SMF set. A request (push procedure, see clause 4.26.2) or response (pull procedure, see clause 4.26.3) from a Source NF/NF Service Instance to a Target NF/NF Service Instance contains either - the context being transferred, e.g. SM context (direct mode); or - optionally, an endpoint address from which Target NF/NF Service Instance can retrieve the context, see TS 29.501[ 5G System; Principles and Guidelines for Services Definition; Stage 3 ]  [62] (indirect mode). It assumes that access to a given context endpoint address can be restricted to single Target NF/NF Service Instance. NOTE: Which procedures need to be executed for indirect mode is part of the specific context transfer procedures as specified in clause 4.26.5.