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Glossary

SIB (System Information Block) in 3GPP: meaning and where it is specified

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

At a glance

Term
SIB
Stands for
System Information Block
Defined in
3GPP TR 21.905 V19.2.0, clause 4
Used in
TS 25.331, TS 34.123-3

In plain words

SIB stands for System Information Block in the vocabulary entry of 3GPP TR 21.905. TS 25.331 uses the term in an information element definition, specifying SIB-Data-fixed as a BIT STRING of SIZE (222). TS 34.123-3 covers scheduling: "The repeat period of broadcasting of a complete SIB configuration is 64 frames (0,64 s) as the default configuration."

Source: 3GPP TS 34.123-3 V18.3.0, clause 8.4. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/34_series/34.123-3/34123-3-i30.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 25.331 V19.0.1, clause 11.3. © 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
  3. 3GPP TS 34.123-3 V18.3.0, clause 8.4. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/34_series/34.123-3/34123-3-i30.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.