Service Request (5G) (5G Service Request Procedure)
The 5G Service Request procedure (3GPP TS 23.502 §4.2.3) is initiated by the UE in CM-IDLE — or by the network via paging — to establish user-plane resources for one or more PDU Sessions and re-activate the N2/N3 tunnels on the AMF and UPF. It is the main state transition between CM-IDLE and CM-CONNECTED and a key measurement point for signaling load.
Categories: Core Network
Service Request (5G) in context
The mobile core carries subscriber sessions, mobility and policy. In 4G it is the EPC (MME, HSS, S/PGW); in 5G it is the Service-Based Architecture with AMF, SMF, UPF, AUSF, UDM and the NRF.
To place Service Request (5G) in the wider telecom-security picture, review PGW, SC, SCP Abuse, SRVCC, N6 and N3: each entry cross-references back to this page so you can walk the topic in either direction.
Related terms
Related topic hubs
- 5G Security 5G SBA, SEPP, SUCI, 5G-AKA, N32 and service-based interface security.
- Diameter Security 4G/LTE Diameter threats across IPX/roaming and DEA defenses.
- Signaling Firewall Unified SS7/Diameter/GTP/SMS signaling firewall framework.
- 5G NEF Security Network Exposure Function security in the 5G core.
More from the TelcoSec Glossary
Browse the full TelcoSec Glossary, the Ultimate Guide to Mobile Network Security, or the P1 Arsenal of telecom-security tools.