TS 55.226 – A5/4 & GEA4 Encryption Algorithms Specification
3GPP TS 55.226 is the 3GPP Technical Specification for A5/4 & GEA4 Encryption Algorithms Specification. It is published in 11 releases (Rel-9 to Rel-19); the latest version is 19.0.0 in Rel-19.
Specifies A5/4 encryption for GSM/ECSD and GEA4 for GPRS/EGPRS. Algorithms are stream ciphers based on KASUMI with 128-bit key length.
Releases and versions of TS 55.226
| Release | Latest version | Links |
|---|---|---|
| Rel-19 | 19.0.0 | Read · Download (3GPP) |
| Rel-18 | 18.0.0 | Read · Download (3GPP) |
| Rel-17 | 17.0.0 | Read · Download (3GPP) |
| Rel-16 | 16.0.0 | Read · Download (3GPP) |
| Rel-15 | 15.0.0 | Read · Download (3GPP) |
| Rel-14 | 14.0.0 | Read · Download (3GPP) |
| Rel-13 | 13.0.0 | Read · Download (3GPP) |
| Rel-12 | 12.0.0 | Read · Download (3GPP) |
| Rel-11 | 11.0.0 | Read · Download (3GPP) |
| Rel-10 | 10.0.0 | Read · Download (3GPP) |
| Rel-9 | 9.0.0 | Read · Download (3GPP) |
Scope of TS 55.226
Category: Security (Encryption). Technology generation: Multi-Gen. Network layer: Security.
Who should read this specification?
- Network operators
- Device manufacturers
- Regulators and standards bodies
Implementation notes
Complexity level: Advanced. Implementation difficulty: Medium.
Key technologies
Other specifications in the 55 series
- TS 55.205 GSM Authentication & Key Generation Example Algorithms
- TS 55.216 A5/3 and GEA3 Encryption Algorithms Specification
- TS 55.217 A5/3 and GEA3 Implementors' Test Data
- TS 55.218 A5/3 and GEA3 Encryption Algorithms
- TS 55.236 A8_V MILENAGE Algorithm for VGCS/VBS Security
- TS 55.241 3GPP Integrity Algorithm GIA4 Specification
- TS 55.242 GIA4 Integrity Algorithm Test Data Specification
- TS 55.243 GIA4 Integrity Algorithm Design Test Data
Related glossary terms
Related topics
Frequently asked questions
What is 3GPP TS 55.226?
3GPP TS 55.226 is the 3GPP Technical Specification for A5/4 & GEA4 Encryption Algorithms Specification. Specifies A5/4 encryption for GSM/ECSD and GEA4 for GPRS/EGPRS. Algorithms are stream ciphers based on KASUMI with 128-bit key length.
Which 3GPP releases include TS 55.226?
TS 55.226 is published in 11 releases, from Rel-9 to Rel-19. The latest version on 3GPP Explorer is 19.0.0 (Rel-19).
What category does TS 55.226 belong to?
TS 55.226 belongs to the Security (Encryption) category of 3GPP specifications. It applies to Multi-Gen networks.
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