# 3GPP TR 26.942 Change Request Summary

## Document Information
- **CR Number**: 0023 rev 1
- **Version**: 19.0.0 → 20.0.0
- **Category**: B (addition of feature)
- **Release**: Rel-20
- **Work Item**: FS_Energy_Ph2_MED
- **Source**: BBC, Orange

## Purpose
This CR proposes normative work and potential further study following the Feasibility Study on energy-related enhancements for media services (5GMS and RTC systems).

## Main Technical Contributions

### 1. General Structure Changes
- Added new normative references:
  - TS 26.512: 5G Media Streaming Protocols
  - TS 26.113: Real-Time Media Communication Protocols and APIs
- Restructured Clause 9 from "Proposed next steps" to "Recommendations" with multiple subclauses

### 2. Recommendations from Version 19 (Clause 9.2)

#### Key Findings
The study identified that normative work on **Key Issue #1 (Energy-related information exposure)** is premature because:
- The Energy Information Function (EIF) defined in TS 23.501 is not yet fully specified
- Capabilities and interfaces of EIF need complete definition first

#### Outstanding Questions Identified
1. **Provisioning mechanisms**: How Application Service Providers provision Information Exposure Specifications in the Energy Information AF (may require PCF/EIF interaction)
2. **Energy Policy concept**: Whether an Energy Policy is needed for ASPs to specify 5GMS System reactions to energy-related information
3. **System reactions**: How 5GMS AS/Client and RTC System functions should react to energy-related information, including:
   - Notification/renegotiation with PCF
   - Modifications to 5GMS AS and Media Stream Handler behavior
   - Dynamic Policy re-instantiation

#### Recommended Approach
A **phased approach** is recommended:
1. Wait for complete EIF definition and TR 22.883 completion
2. Update the TR with:
   - Detailed EIF interaction specifications
   - New Key Issues for unaddressed questions
   - New Key Issues from TR 22.883 use cases
3. Then initiate normative work

#### TR 22.883 Integration
The study will address new use cases on:
- Information exposure of network energy characteristics (consumption, supply mix, carbon footprint, capacity, availability)
- Dynamic service adjustments based on energy characteristics
- Security, charging, and privacy aspects

### 3. Recommendations from Version 20 (Clause 9.3)

#### Core Recommendation
Normative definition and specification of an energy architecture based on **Solution #5**, instantiated in both 5GMS and RTC Systems.

#### Detailed Normative Work Specifications

##### 3.1 New Stage 2 Technical Specification
Define **generic architecture and procedures** for Energy Information AF and Energy Information Collector, covering:
- **E1 reference point**: Provisioning the Energy Information AF
- **E3 reference point**: AS Energy Reports subscription/exposure from Application Servers to Energy Information AF (with baseline parameters)
- **E5 reference point**: Aggregated network energy information exposure from Energy Information AF to Energy Information Collector in UE (with baseline parameters)
- **E6 reference point**: Aggregated energy information exposure from Energy Information Collector to UE Application (with baseline parameters)

##### 3.2 New Stage 3 Technical Specification
Specify **network APIs** for:
- Energy Information AF and Energy Information Collector at E1, E3, E5
- Client API exposed by Energy Information Collector to Application at E6

##### 3.3 TS 26.501 Enhancements (5GMS)
New clauses defining:
- **Architecture instantiation** in 5G Media Streaming System
- **Collaboration scenarios** extending generic procedures for 5GMS-specific Use Cases

##### 3.4 TS 26.506 Enhancements (RTC)
New clauses defining:
- **Architecture instantiation** in RTC System
- **Collaboration scenarios** for RTC-specific Use Cases
- **Note**: Generic scenarios from TS 26.501 may be referenced

##### 3.5 TS 26.512 Extensions (5GMS Protocols)
Specify:
- **Procedure and interface extensions** at E1, E3, E5 for 5GMS System
  - Example: 5GMS AS extracting/exposing energy information from DASH media segments
- **Client API extensions** at M6 reference point (Energy Information Collector in Media Session Handler to 5GMS-Aware Application)

##### 3.6 TS 26.113 Extensions (RTC Protocols)
Specify:
- **Procedure and interface extensions** at E1, E3, E5 for RTC System
  - Example: RTC AS extracting/exposing energy information from RTP header extensions
- **Client API extensions** at RTC-6 reference point (Energy Information Collector in Media Session Handler to RTC-Aware Application)

## Key Architectural Elements

### New Entities
- **Energy Information AF**: Network function for aggregating and exposing energy information
- **Energy Information Collector**: UE-side function for collecting and exposing energy information to applications

### Reference Points
- **E1**: Provisioning interface to Energy Information AF
- **E3**: AS to Energy Information AF interface
- **E5**: Energy Information AF to Energy Information Collector interface
- **E6**: Energy Information Collector to Application interface
- **M6**: 5GMS-specific interface (Media Session Handler to Application)
- **RTC-6**: RTC-specific interface (Media Session Handler to Application)

## Work Item Scope
The CR establishes a comprehensive framework for energy-aware media services spanning:
- Generic architecture applicable to multiple systems
- System-specific instantiations (5GMS and RTC)
- Protocol-level specifications
- Client-side API definitions