Rel-17 & Rel-18 — A Summary of the Key Features of the Latest 5G Releases¶
Learning objectives¶
After reading this chapter, you will be able to:
- Explain the broad picture of how 3GPP releases have evolved: Rel-15 (the first 5G edition) → Rel-16 (increased maturity) → Rel-17 → Rel-18 (5G-Advanced).
- Explain in one line the positioning of the representative 5GC-related features of Rel-17 (RedCap / NPN enhancements / Edge Computing enhancements / NWDAF enhancements / positioning).
- Explain the aims of the representative directions of Rel-18 = 5G-Advanced (AI/ML / eRedCap / energy efficiency / XR / NTN).
- Follow the entry points (links) to the detail page of each feature.
- Understand why the details of "which feature was introduced in which Release" should be treated as to be confirmed, because they vary by version and interpretation.
Prerequisites¶
It will go more smoothly if you understand the following first.
- 5GC overview — the whole picture of the 5G core
- The whole picture of mobile networks — the background of generational evolution
- Supplementary: NWDAF (same level) / RedCap
The nature of this chapter — that it is a survey map
This chapter does not chase individual features deeply; it provides entry points to representative examples as a "map" of the releases. Exactly which Release each feature was introduced in, and the details of spec values, vary by version and interpretation. Rel-18 in particular is still under development, so always treat the details of individual features as to be confirmed against the primary spec (the relevant TS). In this chapter we avoid definitive statements and explicitly note "to be confirmed" and "under development."
Why — why have a "map" of the releases¶
5G was not completed all at once; it evolves through the accumulation of Releases that 3GPP publishes every few years. Even if you memorize only the names of individual features (RedCap, NTN, NWDAF, …), if you cannot see "what era and what problem each of them answered," it becomes hard to make implementation and design decisions.
That is why this chapter aims to have, as a single map, "which release added features in which direction." The goal is to grasp the positioning rather than the details.
Analogy: A release map is a "route map." The interior (detailed spec) of each station (feature) can be looked at at that station; first, get a handle on the whole line (the flow of evolution) and the transfer stations (links to the detail pages).
What — the flow of 3GPP releases¶
We summarize the positioning of each release in one row (the categorization itself is certain as 3GPP's official release definition; the details of when individual features were introduced are to be confirmed).
| Release | Positioning (one line) |
|---|---|
| Rel-15 | The first edition of 5G. Specifies both the NSA (interworking with the existing EPC) and SA (5GC standalone) configurations |
| Rel-16 | Increased maturity of 5G. Brings industrial use (URLLC/TSN), V2X, positioning, etc. into full swing |
| Rel-17 | Functional enrichment such as RedCap, NPN enhancements, Edge enhancements, NWDAF enhancements, and positioning improvements |
| Rel-18 | The starting point of 5G-Advanced. Focuses on directions such as AI/ML, power saving, XR, and NTN |
graph LR
R15[Rel-15
First 5G edition
NSA / SA] --> R16[Rel-16
Increased maturity
URLLC / V2X / Positioning]
R16 --> R17[Rel-17
Functional enrichment
RedCap / NPN / Edge / NWDAF]
R17 --> R18[Rel-18
5G-Advanced
AI-ML / Power saving / XR / NTN]
R18 --> FUT[Rel-19 and beyond
Under development
To be confirmed]
What 5G-Advanced is
It is a marketing/technical name that refers to 5G from Rel-18 onward. The broad picture that Rel-18 is the first release of 5G-Advanced is certain, but which features are taken to be "representative of 5G-Advanced" varies by context. Individual definitive statements are to be confirmed.
How — the representative features of Rel-17 (5GC-related)¶
We narrow to representative examples rather than an exhaustive list. Each feature is kept to a one-liner plus a link.
| Feature | One-line overview | Details / notes |
|---|---|---|
| RedCap (Reduced Capability) |
A category for mid-tier devices with reduced capability (wearables / industrial sensors / surveillance cameras, etc.) | Details deferred to RedCap. The broad picture that RedCap is Rel-17 is certain |
| NPN / SNPN enhancements | Enhancements to non-public networks (private 5G). The framework of SNPN = Standalone NPN (standalone operation) and PNI-NPN (public-network interworking) | The introduction timing of individual enhancement items is to be confirmed |
| Edge Computing enhancements | A framework for discovering and connecting to edge-deployed apps (EAS / EES / ECS, etc.) | The framework is certain per TS 23.548. The details are to be confirmed |
| NWDAF enhancements | Enrichment of the network data analytics function (e.g., a framework related to providing ML models) | Details deferred to NWDAF (same level) / NWDAF (NF detail). Version differences of individual enhancements are to be confirmed |
| Positioning improvements | The direction of improving positioning accuracy and latency | Details of specific accuracy values and methods are to be confirmed |
The Edge Computing framework (EAS/EES/ECS)
- EAS (Edge Application Server): the app body itself running at the edge
- EES (Edge Enabler Server): assists app discovery and connection on the edge side
- ECS (Edge Configuration Server): provides the configuration for which EES to use
These frameworks are specified in TS 23.548 (architecture). The detailed section numbers of each procedure differ by version, so when citing precisely, treat them as to be confirmed.
How — the representative directions of Rel-18 (5G-Advanced)¶
Rel-18 is newly under development. The following are "representative examples of the focus directions," and you should treat the detailed spec values of individual features as to be confirmed with particular care.
| Direction | One-line overview | Notes (degree of to-be-confirmed) |
|---|---|---|
| AI/ML and automation enhancements | Expanded application of AI/ML to NR and network operations, and deepened automation | The framework including NWDAF cooperation is in progress. Details to be confirmed. For the analytics platform, see NWDAF (same level) |
| eRedCap (further cost reduction) | A derivative direction making RedCap even lower-cost and lower-capability | The naming and scope vary by version. To be confirmed. For the basics, see RedCap |
| Energy efficiency (Network Energy Saving) |
The direction of treating base-station/network power saving as a standard | Specific methods and metrics are under development. To be confirmed |
| XR / media enhancements | Handling the traffic characteristics of extended reality (XR) and high-load media | Details of the scope are to be confirmed |
| Positioning / NTN enhancements | Further improvement of positioning, and enhancement of NTN (non-terrestrial = satellites, etc.) | The scope and supported bands of NTN are under development. To be confirmed |
Handling of Rel-18 — avoid definitive statements
The items in the table above are representative examples of "directions being intensively addressed in Rel-18." How individual features are defined and which values they take in the final spec may change depending on the state of development. In design and implementation decisions, always treat them as to be confirmed against the latest version of the relevant TS. This chapter sticks to presenting entry points.
The positioning of this chapter (dedup boundary)¶
This chapter is a "release map." Deep content is deferred to each detail page.
- Details of RedCap → RedCap
- Details of NWDAF / Analytics → NWDAF (same level) and NWDAF (NF detail)
- Release differences in individual areas such as charging are described within each chapter (e.g., the "Release differences" of Charging)
3GPP Specification¶
| Spec | Content |
|---|---|
| TS 23.548 | 5G System Enhancements for Edge Computing (Edge: the EAS/EES/ECS framework) |
Reference granularity and to be confirmed
The release categorization itself is certain as 3GPP's official definition. TS 23.548 in the table above is certain as the Edge Computing framework, but the detailed section numbers within each TS differ by version. Which Release an individual feature was introduced in, and the details of spec values, have some variability, so when citing precisely, always treat them as to be confirmed against the relevant version of the relevant TS (Rel-18 in particular is under development).
FAQ¶
Q. Do "5G-Advanced" and "Rel-18" mean the same thing?
They are used almost synonymously, but strictly, 5G-Advanced = 5G from Rel-18 onward is the name, and Rel-18 is its first release. Which features are called "representative of 5G-Advanced" varies by context, so individual definitive statements are to be confirmed.
Q. Is it okay to assert that a certain feature "was introduced in Rel-17"?
The broad picture such as RedCap = Rel-17 and 5G-Advanced = Rel-18 is certain. However, in which Release individual fine features or spec values were settled can vary by version and interpretation. In this chapter, we mark items we cannot be certain of as to be confirmed.
Summary¶
- 3GPP evolves through accumulation: Rel-15 (first edition) → Rel-16 (increased maturity) → Rel-17 → Rel-18 (5G-Advanced).
- Representatives of Rel-17: RedCap / NPN・SNPN enhancements / Edge enhancements (EAS/EES/ECS, TS 23.548) / NWDAF enhancements / positioning improvements.
- Representative directions of Rel-18 (5G-Advanced): AI/ML and automation / eRedCap / energy efficiency / XR / positioning and NTN.
- The release categorization is certain, but the introduction timing of individual features and the details of spec values are to be confirmed (Rel-18 in particular is under development).
- This chapter is a "map"; the details are deferred to each page (RedCap, NWDAF, etc.).
Comprehension check¶
Q1. Explain the positioning of each release from Rel-15 to Rel-18 in one line each.
Rel-15 = the first 5G edition (NSA/SA), Rel-16 = increased maturity (URLLC/V2X/positioning), Rel-17 = functional enrichment (RedCap/NPN/Edge/NWDAF), Rel-18 = the starting point of 5G-Advanced (AI/ML/power saving/XR/NTN). The categorization is certain, but the details of individual features are to be confirmed.
Q2. State the roles of EAS / EES / ECS that appear in the Rel-17 Edge Computing enhancements, and the spec you can reliably reference.
EAS = the app body running at the edge, EES = assists app discovery and connection on the edge side, ECS = provides the configuration for which EES to use. The framework is specified in TS 23.548 (the detailed section numbers are to be confirmed).
Q3. When describing Rel-18 features, why should you actively attach "to be confirmed" and "under development"?
Because Rel-18 = 5G-Advanced is newly under development, and the final definitions and spec values of individual features may change. Even if the broad picture (Rel-18 being the starting point of 5G-Advanced) is certain, asserting the details is prone to error, so they should be treated as to be confirmed against the primary spec.
Next Step¶
- Dig deeper into the details of reduced-capability devices in RedCap.
- Learn the details of network analytics in NWDAF (same level).
- To go back to the basics, head to 5GC overview / The whole picture of mobile networks.