3gpp Specifications

3GPP Specifications

Overview

3GPP specifications are the primary deliverables of the 3GPP partnership. They include:

• Technical Specifications (TS) - Normative technical documents
• Technical Reports (TR) - Informative studies and reports

TS vs TR Distinction

TS (Technical Specification)

• Purpose: Define requirements, protocols, and interfaces
• Status: Can be revised via Change Requests (CRs)
• Format: Word™ (.doc) and Zip™ archives
• Numbering: 21.456 (Series + Spec number)
• Authority: Produced by WG or TSG

TR (Technical Report)

• Purpose: Informative studies, analysis, or background information
• Status: Fixed at publication, can be revised via CRs
• Format: Word™ (.doc) and Zip™ archives
• Numbering: TR 21.900 (TR + number)
• Authority: Produced by WG or TSG

Numbering Scheme

Format

Two-digit series number + Three-digit spec number:

<series>.<spec>

Examples:

• TS 21.456 - Series 21, spec 456
• TS 22.101 - Series 22, spec 101
• TR 21.900 - Technical Report 21, number 900

Specification Series Meanings

Each two-digit series corresponds to a specific technical domain:

Key patterns:

• Series 21-24: Core requirements, services, architecture, signalling
• Series 25, 36-38: Radio technologies (UTRA → LTE → NR)
• Series 31-35: Security and terminal testing
• Series 26, 32: Media codecs and network management

Document Type Prefixes

• TS: Technical Specifications (normative)
• TR: Technical Reports (informative)

Spec File Formats

Word™ Format

• Purpose: Formal specification document for review and change
• Extension: .doc
• Structure: Can include revision marks ("Track Changes")

Zip™ Format

• Purpose: Archive format for distribution
• Extension: .zip
• Contents: Word™ .doc files and additional resources

FTP Directory Structure

Root Directory

https://www.3gpp.org/ftp/Specs/<YYYY>-<MM>/

TSG Round Examples:

• RAN#110: https://www.3gpp.org/ftp/Specs/2025-12/
• SA#110: https://www.3gpp.org/ftp/Specs/2025-12/
• CT#110: https://www.3gpp.org/ftp/Specs/2025-12/SpecslistexTSG/TSG110.htm

Directory Contents

Each TSG round directory contains:

• HTML index pages (SpecslistexTSG/TSG#>.htm)
• Individual spec files (.doc, .zip)
• Delta directories for parallel releases (e.g., 21.101d)
• CR database and work item references

Spec Categories

Major Categories

• GSM (including GPRS and EDGE)
• W-CDMA (including HSPA)
• LTE (including LTE-Advanced and LTE-Advanced Pro)
• 5G (including 5G NR Standalone)

Spec Numbering Pattern

When a new spec is created:

1. Allocated next sequential spec number
2. Example: If last spec in series 21 is 21.456, next is 21.457
3. Continues until end of series or major release change

Example:

Series 21: 21.001, 21.002, 21.003, ..., 21.456
Series 22: 22.001, 22.002, 22.003, ..., 22.101

Spec Files

File Naming Convention

Spec files follow 3GPP naming conventions:

• Series number and spec number
• Type identifier (TS/TR if applicable)
• Version number (for revised versions)
• Language code (if multilingual)

Example:

• 21.456.doc - TS 21.456 Word™ document
• 21.456.zip - Zip™ archive containing Word™ files
• 21.456_003.doc - Version 003 revision

Working Groups and Specs

Working Group Responsibility

Each Working Group is responsible for specifications in their domain:

• RAN: Radio access technologies
• SA: System architecture and services
• CT: Core network and terminals

Spec Assignment

Specs are assigned to Working Groups based on their scope:

• Technical specs typically belong to specific WGs
• TSG plenaries approve specs for all TSGs

Release Management

MCC (Mobile Competence Centre)

The MCC aims to make all specs available following TSG round as soon as possible.

Target Dates

• Standard: 4 weeks after TSG plenary
• Extra time: Additional week for large volumes or holiday periods

Version Control

Spec Versions

• Initial version: When first published as TS/TR
• Revisions: Numbered versions created via Change Requests
• Dot notation: Decimal numbering (e.g., 21.456.1)

Example Revision Numbering:

• Initial: 21.456
• First revision: 21.456.1
• Second revision: 21.456.2
• Third revision: 21.456.3

Version Number Format

Spec version numbers follow the format: <series>.<version>

Examples:

• 21.456.0 - Initial version of spec 21.456
• 21.456.1 - First revision of spec 21.456
• 22.101.3 - Third revision of spec 22.101

Database References

CR Database

Change Requests are tracked in a database accessible via:

• Netovate Search: Free CR database search tool
• Portal CR Database: 3GPP portal CR database
• Spec History: Each spec's history lists all approved CRs

Work Items

3GPP Work Items define features to be developed. New specs and CRs are linked to Work Items.

Key Points

• Spec Numbering is hierarchical: Series → Spec Number
• TR numbers are separate series: Use TR prefix for reports
• Revisions create new versions: Each CR creates a new version number
• Multiple CRs can affect one spec: All are merged into single version
• Mirror CRs require same WI code: For specs in multiple releases

Cross-References

• 3gpp-releases - For release structure and freeze concepts
• 3gpp-working-groups - For understanding which WG owns which specs
• 3gpp-change-request - For modification process via CRs
• 3gpp-meetings - For understanding when specs are approved (at TSG plenaries)

Resources

• 3GPP Official: https://www.3gpp.org/
• 3GPP Portal: https://portal.3gpp.org/
• 3GPP Work Plan: https://www.3gpp.org/specifications-technologies/3gpp-work-plan/
• MCC Info: Available in spec list tables

Usage in Code

Finding Spec Files

import requests
from bs4 import BeautifulSoup

# FTP directory for Release 18
base_url = "https://www.3gpp.org/ftp/Specs/2018-12/"
response = requests.get(base_url)
soup = BeautifulSoup(response.text, "html.parser")

# Parse all spec files
for link in soup.find_all("a", href=True):
    href = link.get("href")
    if href.endswith(".doc") or href.endswith(".zip"):
        print(f"Found spec: {href}")

Spec Number Parsing

import re


def parse_spec_number(filename: str) -> tuple:
    """Parse spec number from filename."""
    # Extract series number and spec number
    match = re.match(r"(\d{2})(\d{3})(\.doc|\.zip)", filename)
    if not match:
        return (None, None)

    return (match.group(1), match.group(2))

Common Patterns

Delta Directories

For parallel releases (e.g., Rel-4/5/6), 3GPP creates delta directories containing only changed specs.

Purpose: Reduce duplicate storage and make it easy to identify what's new in each release.

Versioning in Practice

• Dot notation: Use decimal versions for clarity (e.g., 21.456.1)
• Editorial changes: Occasionally updated by MCC, not versioned
• Major/minor changes: Some specs have major version increments between releases

Related Documents

• Versioning Scheme: https://www.3gpp.org/specifications-technologies/specifications-by-series/version-numbering-scheme
• Work Items: https://www.3gpp.org/specifications-technologies/3gpp-work-plan/what-is-a-work-item