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3GPP Spec Finder & Series Guide

Type a 3GPP spec number (e.g. 38.331, 23.501, 24.501) to get its title and series, or browse the series guide — 5G NR, NAS, core, security and LTE.

📚 3GPP TS/TR numbering · series 21–38

Try a number (23.501), a series (38), or a word (RRC, PDCP, charging).

Reference3GPP series guide

SeriesTopic
21-seriesRequirements (general)
22-seriesService aspects (stage 1)
23-seriesTechnical realization / architecture (stage 2)
24-seriesSignalling protocols, UE–network (NAS, stage 3)
25-seriesRadio aspects (UMTS / UTRAN)
26-seriesCODECs
28-seriesTelecom management, charging & OAM
29-seriesSignalling protocols, core network (SBI, stage 3)
31-seriesUICC / USIM
32-seriesOAM&P and charging
33-seriesSecurity
35-seriesSecurity algorithms
36-seriesLTE / E-UTRA(N) radio
37-seriesMultiple radio access (E-UTRA & NR)
38-series5G NR & NG-RAN radio
51-seriesGSM/EDGE radio

ReferenceCommon 5G & LTE specifications

SpecTitleSeries
TS 21.905Vocabulary for 3GPP Specifications21-series
TS 22.261Service requirements for the 5G system (stage 1)22-series
TS 23.003Numbering, addressing and identification23-series
TS 23.122NAS functions related to MS in idle mode (PLMN selection)23-series
TS 23.401GPRS enhancements for E-UTRAN access (EPC, LTE)23-series
TS 23.501System architecture for the 5G System (5GS); stage 223-series
TS 23.502Procedures for the 5G System (5GS); stage 223-series
TS 23.503Policy and charging control framework for the 5GS; stage 223-series
TS 24.301NAS protocol for EPS (LTE); stage 324-series
TS 24.501NAS protocol for 5GS (5G NAS); stage 324-series
TS 28.531Management and orchestration; provisioning28-series
TS 29.244Interface between control and user plane nodes (PFCP)29-series
TS 29.5005GS; Technical realization of Service Based Architecture; stage 329-series
TS 29.5025GS; Session Management Services (Nsmf)29-series
TS 29.5035GS; Unified Data Management Services (Nudm)29-series
TS 31.102Characteristics of the USIM application31-series
TS 32.2555G data connectivity domain charging32-series
TS 33.501Security architecture and procedures for the 5G System33-series
TS 35.205MILENAGE algorithm set (authentication)35-series
TS 36.211E-UTRA (LTE); Physical channels and modulation36-series
TS 36.300E-UTRA and E-UTRAN; Overall description; stage 236-series
TS 36.331E-UTRA (LTE); Radio Resource Control (RRC) protocol36-series
TS 37.340Multi-connectivity; Overall description (EN-DC); stage 237-series
TS 38.101NR; User Equipment (UE) radio transmission and reception38-series
TS 38.104NR; Base Station (BS) radio transmission and reception38-series
TS 38.211NR; Physical channels and modulation38-series
TS 38.212NR; Multiplexing and channel coding38-series
TS 38.213NR; Physical layer procedures for control38-series
TS 38.214NR; Physical layer procedures for data38-series
TS 38.300NR and NG-RAN; Overall description; stage 238-series
TS 38.321NR; Medium Access Control (MAC) protocol38-series
TS 38.322NR; Radio Link Control (RLC) protocol38-series
TS 38.323NR; Packet Data Convergence Protocol (PDCP)38-series
TS 38.331NR; Radio Resource Control (RRC) protocol38-series
TS 38.401NG-RAN; Architecture description38-series
TS 38.413NG-RAN; NG Application Protocol (NGAP)38-series
TS 38.423NG-RAN; Xn Application Protocol (XnAP)38-series
TS 38.473NG-RAN; F1 Application Protocol (F1AP)38-series

A curated set of the most-referenced specs. The full catalogue lives at the 3GPP specifications portal.

FAQFrequently asked questions

What does the 3GPP TS 38 series cover?
The 38-series covers 5G NR and the NG-RAN — the radio physical layer (38.211–38.214), the L2/L3 protocols (38.321 MAC, 38.322 RLC, 38.323 PDCP, 38.331 RRC) and the RAN interfaces (38.401, NGAP/XnAP/F1AP).
Which 3GPP spec defines the 5G core architecture?
TS 23.501 (System architecture for the 5G System, stage 2) defines the 5G core architecture; TS 23.502 defines the procedures, and TS 23.503 the policy/charging framework.
What is the difference between a TS and a TR?
A TS (Technical Specification) is normative — it defines what must be implemented. A TR (Technical Report) is informative — a study or background document that does not impose requirements.
Which spec defines 5G security?
TS 33.501 (Security architecture and procedures for the 5G System) is the master 5G security spec, covering primary authentication (5G-AKA), the key hierarchy, SUCI/SUPI concealment and network-domain security.

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