Overview¶

Summary

These 5G notes are designed for anyone who wants to learn 5G.
The focus is on easy understanding first, while also providing deeper paths and reference links if you want to explore specific topics further.

So, enjoy the 5G journey!

Tip

Each page starts with the big picture, then moves into protocol-level or more intuitive explanations to help you build understanding.
After that, it may go deeper into specific areas such as protocols and physical layer details.

5G SA Call Flow — Video Walkthrough¶

5G System Architecture¶

Figure 1. Open5GS 4G/5G NSA and 5G SA System Architecture, showing Control/User Plane Separation (CUPS)¹

This is the diagram behind the Try 5G Yourself lab, and it's a genuinely good one-page summary of how a 5G SA core fits together:

The Full SA Attach Flow¶

Useful Resources¶

Open5GS Quickstart — source of the architecture diagram above
3GPP TS 23.502 — Procedures for the 5G System: the authoritative source for the full attach flow
Techplayon — 5G NR SA Registration / 5G Call Flow
ShareTechnote — Mobile Communication - Signal Flow

Lee, S. (n.d.). Quickstart [Architecture diagram]. Open5GS. https://open5gs.org/open5gs/docs/guide/01-quickstart/ ↩
Techplayon. (n.d.). 5G SA registration / 5G call flow. Techplayon. https://www.techplayon.com/5g-nr-sa-registration-attach-call-flow/ ↩