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3GPP Specifications for UMTS

25 series - Radio interface access stratum protocols and the radio access network 27 series - R interface protocols and terminal adaptation functions 28 series - Tandem-free operation of speech codecs 26 series - Codecs 31 series - Cu interface protocols, UICC and USIM 30 series - Programme management 21 series - Requirements 35 series - Cryptographic algorithms 33 series - Security 34 series - UE conformance tests 21.905 - Vocabulary for 3GPP Specifications 21.101 - Technical Specifications and Technical Reports for a UTRAN-based 3GPP system


The 3rd generation partnership project (3GPP) maintains several hundred specifications that define the operation of UMTS and GSM. This section of the website is a summary of the UMTS specifications and a visual interface to them.

A typical 3GPP specification number looks like this:

TS 25.331 v5.17.0


TSstands for technical specification. Other documents are known as technical reports, and denoted TR.
25is the series number. The specifications are organised into series that cover different parts of the system. Series 21 to 36 are used by UMTS, while other series are only used by GSM.
25.331is the specification number. (This particular specification defines a protocol known as radio resource control (RRC)).
5is the release number. Each release is a version of the system with a particular set of features. 3GPP maintains specifications for all the releases in parallel, so that they can add new features to the system while still giving manufacturers a stable implementation platform.
17is the technical version number. This is incremented after technical changes to a specification. The latest technical version is usually the only one of interest.
0is the editorial version number. This is usually 0, but is sometimes incremented after editorial changes.

(A few specifications are divided into parts or even subparts. For example, TS 29.198-04-1 is TS 29.198 part 4 subpart 1.)

You can navigate the website by following the links shown in blue above. The site currently includes links to the technical specifications from release 99 up to release 7 in the indicated series, together with a few of the most useful technical reports. Other series and releases will be added in due course. You can select the release of interest using the pull-down menu on the left: the website will find the latest technical and editorial version automatically.

3GPP produces revised versions of the specifications four times a year, after its quarterly TSG plenary meetings. The material here was last updated after the TSG plenary meeting in December 2006.


3GPP3rd generation partnership project
GSMGlobal system for mobile communications
MEMobile equipment
MTMobile termination
TETerminal equipment
TRTechnical report
TSTechnical specification
TSG Technical specification group
UEUser equipment
UICCUniversal integrated circuit card
UMTSUniversal mobile telecommunication system
UTRANUMTS terrestrial radio access network
USIMUniversal subscriber identity module


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