eSIM RSP Knowledge Base

Comprehensive technical knowledge base covering 12 GSMA eSIM specifications. 84+ articles on Remote SIM Provisioning — SGP.02, SGP.22, SGP.32, SGP.41, SGP.29, SGP.23, SGP.25, SGP.26 and more.


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The Ultimate Safety Inspection: SAS-UP 🏭✅

Imagine…

You’ve designed the world’s safest car seat. It passed every crash test, every material check, every durability trial. But there’s one more hurdle: an inspector visits the factory where it’s made. They check that the assembly line doesn’t mix up parts, that workers follow safety protocols, and that every seat coming off the line is identical to the one that passed testing.

A brilliant design made in a sloppy factory is NOT a safe product.

This is the logic behind SAS-UP : the Security Accreditation Scheme for UICC Production. It’s the final check that transforms a tested eUICC design into a production-ready chip.


The Six-Stage Certification Journey 🗺️

Stage What Happens
1. Declaration Chip maker fills out the Optional Features Table (30+ options) and provides IUT Settings
2. Applicability The Applicability Table determines exactly which tests apply (Mandatory, Conditional, or Not Applicable)
3. Execution Tests run in TE_eUICC or TE_Integrated eUICC environment
4. Results Each test gets Pass, Fail, or Inconclusive (infrastructure problems don’t count against the chip!)
5. SAS-UP Link The sasAcreditationNumber in the chip’s response is verified against the accredited factory
6. DLOA Digital Letter of Approval issued by GlobalPlatform

The Declaration: What Can Your Chip Do? 📋

Before testing starts, the vendor fills out an honest self-assessment:

Category Example Options
Encryption Curves NIST P-256, BrainpoolP256r1, FRP256V1, SM2
LPA Features Built-in LPAe, LPA Proxy support
Profile Features Remote Profile Management, Enterprise Profiles, Device Change, OS Update
MEP Modes MEP-A1, MEP-A2, MEP-B, MEP-B without Refresh
Form Factor Standard removable chip or Integrated (SoC-embedded)

If a vendor supports both “with” and “without” a feature (providing different chip samples), the test tool runs all applicable tests for each sample independently.


Applicability: The Smart Filter 🧠

The Applicability Table uses logic to decide which tests to run:

This means a simple chip gets a manageable test suite, while a feature-packed chip gets a comprehensive one.


Pass, Fail, or Inconclusive? 🤔

SGP.23-1 is fair about failures:

Result Meaning
Pass Every step produced the expected result
Fail The chip did something unexpected at some step
Inconclusive ⚠️ The test couldn’t finish because of setup problems: NOT the chip’s fault!

The inconclusive category prevents false negatives. If the test tool has a bug or the card reader glitches, the chip isn’t penalised.


SAS-UP: The Factory Check 🏭

SAS-UP doesn’t test the chip design: it audits the manufacturing site:

The link between testing and manufacturing is the sasAcreditationNumber : a unique identifier embedded in every production chip that SGP.23-1 test cases explicitly verify.


The Final Prize: DLOA 🏆

When all applicable tests pass, the Digital Letter of Approval is issued:


The Layered Trust Model 🧅

eSIM certification is like an onion: layers of trust, each depending on the layer below:

  1. SAS-UP certifies the factory
  2. SGP.23-1 certifies the chip from that factory
  3. SGP.23 uses the certified chip to test everything else
  4. Operators trust the whole stack because every layer has been independently verified

The GSMA runs regular Test Events where vendors bring their implementations for formal assessment. SGP.23-1’s document history shows Change Requests flowing in from these events: each one fixing an ambiguity that real testers discovered. The specification has evolved from v2.0 (2018) through v3.1.3 (2025) based on actual testing experience!


Kid-friendly version of GSMA SGP.23-1, Sections 2.1, 2.2, 3, Annexes F, G, L; GlobalPlatform GPC_SPE_095

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