3GPP TR 26.942 Change Request - Solution for Key Issues #5 and #6

General Information

• CR Number: 0014 rev 5
• Current Version: 19.0.0
• Release: Rel-20
• Category: B (addition of feature)
• Work Item: FS_Energy_Ph2_MED
• Source: Nokia

Purpose

This CR proposes Solution #11(b) addressing:
- Key Issue #5: Media Application Server Energy management
- Key Issue #6: Client-driven management of media delivery service energy optimisation

References Added

New normative references added:
- [36300]: TS 36.300 - E-UTRA and E-UTRAN Overall description
- [28558]: TS 28.558 - UE level measurements for 5G system
- [23288]: TS 23.288 - Architecture enhancements for network data analytics services

Solution Overview (Clause 7.13)

Key Concept

The solution enables Media AS service endpoint reselection during an active media delivery session based on:
- UE application QoE requirements (resolution, bit rate, etc.)
- Energy-related characteristics of individual Media AS service locations (load, energy consumption, QoE metrics)

Framework Basis

• Leverages QMC-based QoE reporting framework (Clause 4.2.2.2)
• Based on Option 1 from Solution #6 (Clause 7.7.3.1.2)
• Uses existing OAM capabilities for exposing KPIs, performance metrics, and energy data via SBMA framework (TS 28.533, TS 28.532)
• Extends edge processing interfaces from TS 26.501 (5GMS) and TS 26.506 (RTC)

Architecture Components

Energy Information AF (EIAF):
- Instantiated in Media AF
- Evaluates energy consumption and efficiency for ongoing media services
- Uses energy-related parameters provisioned via M1
- Provides energy-related indications/recommendations to Media AF when thresholds are crossed
- Correlates QoE information with service-level and media-level energy information

Energy Information Collector (EIC):
- Instantiated in Media Session Handler of UE Media Client
- Receives information via E5 for correlation with QoS/service information
- Provides feedback to Media Application Provider via M8
- Does not directly influence media adaptation decisions (controlled by Media AF)

AS Energy Report Reuse

The solution reuses the Application Server (AS) Energy Report for consistent reporting:

Reused elements:
- Energy consumption and efficiency indicators → mapped to EnergyConsumptionValue and EnergyEfficiencyMetric
- Reporting scope and aggregation level → determines EnergyMeasurementScope
- Reporting triggers and reasons → reflected in EnergyReportingReason
- Reporting timing and validity → reused for EnergyMeasurementTime, EnergyInformationTimestamp, EnergyReportValidityTime

The Energy Information AF combines AS Energy Report information with additional context (QoS degradation, QoE metrics from OAM, policy constraints from M1) to derive consolidated energy-related information conveyed via E5.

Energy-Related Information Parameters

7.13.5.1 Energy-Related Provisioning Information (via M1)

Parameters provisioned to Energy Information AF:

| Parameter | Description |
|-----------|-------------|
| Energy Policy identifier | Identifies the energy policy instance |
| Energy monitoring Configuration scope | Scope and granularity (per service/session/component) |
| Energy reporting configuration | Reporting conditions (frequency, threshold triggers) |
| Energy thresholds | Threshold values for consumption/efficiency |
| Energy adaptation guidance | Recommended energy-aware adaptation actions (codec selection, rate reduction, etc.) |
| Energy suspension policy | Conditions for suspending media components/sessions |
| Energy recovery policy | Conditions permitting increased energy consumption |
| Energy reporting recipient | Entities receiving energy reports/notifications |
| Service energy profile | Energy efficiency profile for service/application |
| Energy Measurement Time | Time/interval for measurements |
| Energy Report Validity Time | Validity period for reported information |

7.13.5.2 Client Energy Reporting Information (via E5)

Parameters conveyed from Energy Information AF to Energy Information Collector:

| Parameter | Description |
|-----------|-------------|
| Energy Policy identifier | Identifies applicable energy policy |
| Application Identifier | Service/application/media session group |
| Energy measurement scope | Scope of reported information |
| Energy measurement time | Time/interval of measurement |
| Energy threshold status | Whether thresholds crossed |
| Energy budget status | Current budget status |
| Energy adaptation status | Whether adaptation actions applied |
| Energy reporting reason | Reason for reporting |
| EnergyReportValidity time | Validity period |
| EnergyInformationTimestamp | Generation timestamp |
| Energy Adaptation Recommendation | Recommended energy-related actions |
| EnergyConsumptionValue | Measured/estimated consumption |

Procedures (Clause 7.13.6)

Energy Information Collection Provisioning (Steps 1-8)

1. Media Application Provider provisions Media AF via M1, including Energy Information exposure configuration and Energy Policy
2. (Omitted - NF Energy Reports not required)
3. Energy Information AF configures AS Energy Information reporting in Media AS via E3
4. Media AS submits AS Energy Information report to Energy Information AF via E3
5. Media-aware Application initiates media delivery session with Media Session Handler via M6
6. Media Session Handler obtains Service Access Information from Media AF
7. Media Session Handler creates energy-related information collection context with Energy Information Collector
8. Energy Information Collector subscribes to Network Energy Information reporting from Energy Information AF via E5

Application Layer QoE Measurement Configuration (Steps 10a-10g)

Follows TS 38.300 Clause 21.2.1 (management-based QMC activation):

• 10a: OAM sends QoE configuration request to RAN/gNodeB
• 10b: gNodeB forwards application layer measurement configuration to UEs in RRCReconfiguration message
• 10c: Media Session Handler subscribes to QoE metrics from Media Access Function at M11
• 10d: UE sends application layer measurement reports to gNodeB in MeasurementReportAppLayer message
• 10e: gNodeB forwards to OAM
• 10f: OAM forwards UE Application Layer QoE measurement to Media AF (if subscribed)
• 10g: Energy Information AF and Media AF map UEs with Media AS service locations based on BaseURL and reported metrics

Initial Configuration (Steps 11-19)

1. Energy Information AF sends initial configuration to UE Media Client with list of available Media AS service location endpoints via M5
2. Media Entry Points returned to Media-aware Application
3. Media-aware Application selects Media Entry Point based on available service locations
   17-19. Media delivery started, Media Entry Point retrieved from selected service location (e.g., "SL1")

Reporting Application Server Metrics (Steps 30-31d)

• 30: Media AS exposes AS Energy Information Report to Energy Information AF via E3
• 1319: Energy Information AF processes received energy-related information about service locations
• 31a-31d: Ongoing application layer measurement reporting (UE → gNodeB → OAM → Media AF), mapping UEs to service locations

Media Session Adaptation (Steps 2132-35g)

• 2132: Energy Information AF sends new configuration to UE Media Client with updated service location endpoints
• 35: Media Session Handler selects service endpoints based on E5 information
• 2235a: Media Session Handler selects new Media AS service location without modifying ongoing session
• 2435b: Media Session Handler requests Media Access Function to switch to new service location
• 2535c: New media delivery transport session established with new service location (e.g., "SL2")
• 2635d: Media Access Function notifies Media Session Handler of successful establishment
• 35e: Media Session Handler relays notification to Energy Information Collector
• 35f: Energy Information Collector notifies Energy Information AF about service location modification
• 2735g: Media delivery continues via new service location

Gap Analysis (Clause 7.13.7)

Identified gaps in Release 19 specifications (in addition to Solution #5 gaps):

1. Step 10c: Ability for Media Access Function to report initial QoE metrics to Media Session Handler for ongoing sessions
2. Step 10/10g: Ability for Energy Information AF and Media AF to map UEs with Media AS service locations based on base URL and reported metrics
3. Steps 11-12: Ability for Energy Information AF to send initial configuration to UE Media Client with available service location endpoints
4. Step 15: Ability for Media Session Handler to provide Energy Information for each Media Entry Point to Media-aware Application at M6
5. Step 16: Ability for Media-aware Application to select Media Entry Point according to energy-related characteristics
6. Step 35: Ability for Media Stream Handler to select Service Operation Point based on configuration from Media Session Handler

Proposed Normative Changes (Clause 7.13.8)

Beyond Solution #5 normative work, additional changes to TS 26.512:

New Clauses Required

a) Extensions to M11 procedures and service-based interfaces for:
- Media Access Function reporting initial QoE metrics to Media Session Handler for ongoing sessions

b) Extensions to M11 procedures and service-based interfaces for:
- Energy Information AF and Media AF mapping UEs to Media AS service locations based on base URL, UE-related metrics, and AS Energy Report information

Summary (Clause 7.13.9)

The solution describes:
- Exposure of energy-related information about different service locations from Media AS to Media AF
- Exposure of this information to UE application during media delivery session
- Dynamic reselection of Media AS service locations during ongoing M4 sessions based on:
- UE application QoE requirements
- Energy-related characteristics from Media AS service locations
- Mechanism enabling Media Client to dynamically select most energy-efficient service location
- Interaction between Energy Information AF and Media Client for joint selection based on network and UE energy information

Applicability: Downlink media sessions, uplink media sessions, and RTC communication sessions

Key Factors:
1. Energy efficiency metrics from Network Operator (power consumption profiles, energy performance indicators from Media AS service locations)

Approach: Optimizes energy consumption of multimedia content delivery while maintaining service quality, operating entirely within network layer using standard adaptive streaming frameworks for compatibility with existing ecosystems.