Hi everyone,
I’ve recently published an animated explainer video that walks through the subscriber authentication process in 3G (UMTS) mobile systems. It’s designed for telecom professionals who want a clear, visual breakdown of how IMSI, USIM, and cryptographic functions (f1–f5) work together to ensure secure access.
Key Highlights:
- IMSI structure and its role in identity management
- USIM internals: secret key, RAND, SQN, AMF
- Generation of authentication vectors: RAND, AUTN, SRES, CK, IK
- Mutual authentication between mobile station and network
- Role of MSC/VLR, HLR, and AuC in the authentication flow
Watch the video here: https://youtu.be/h9l7JuUfybE
This is part of a series—if you missed the 2G authentication video, I recommend checking that out first for foundational context. The next one will cover 4G (LTE) authentication.
Would love to hear your feedback or suggestions for future topics!