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Glossary

C-RNTI (Cell Radio Network Temporary Identity) in 3GPP: meaning and where it is specified

Published 2026-10-16Updated 2026-10-16

At a glance

Term
C-RNTI
Stands for
Cell Radio Network Temporary Identity
Defined in
3GPP TR 21.905 V19.2.0, clause 4
Other meanings in TR 21.905
Cell RNTI
Used in
TS 25.331, TS 25.423, TS 36.401

In plain words

3GPP TR 21.905 expands C-RNTI as Cell Radio Network Temporary Identity, and TS 25.423 also calls it Cell RNTI. In TS 25.423, it is a UE identifier allocated by the DRNS for use over the radio interface. TS 25.331 describes its cell scope, and TS 36.401 says "The C-RNTI provides a unique UE identification at the cell level identifying RRC connection.".

Source: 3GPP TS 36.401 V18.1.0, clause 6.2.8.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/36_series/36.401/36401-i10.zip

Sources

  1. 3GPP TR 21.905 V19.2.0, clause 4. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/21_series/21.905/21905-j20.zip
  2. 3GPP TS 25.423 V19.0.0, clause 9.2.1.14. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/25_series/25.423/25423-j00.zip
  3. 3GPP TS 25.331 V19.0.1, clause 10.3.3.8. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/25_series/25.331/25331-j01.zip
  4. 3GPP TS 36.401 V18.1.0, clause 6.2.8.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/36_series/36.401/36401-i10.zip

How this page was made

The facts box comes straight from the 3GPP TDoc list and specification archive as indexed by 3GPP Scout. An AI model (GPT-6 Luna) wrote the paragraph and named the source of each sentence. Code checked every quote word for word against the stored source text and every number against the cited source. A second AI model from another company (Claude Opus 5.5) reviewed the paragraph against the same sources. The 3GPP documents themselves govern.