# LS on Traffic Model for Immersive Communication

## Document Information
- **Source:** RAN WG1
- **Target:** SA WG4
- **Meeting:** RAN1 #123 (Dallas, USA, November 17-21, 2025)
- **Release:** Rel-20
- **Work Item:** FS_6G_Radio

## Overall Description

RAN1 has developed traffic models for immersive communications services based on 6G radio evaluations. The work builds upon the existing XR traffic model defined in TR 38.838, with amendments to support immersive communication use cases.

## Technical Contributions

### Model-1: eXR Model without Haptics

This model extends the existing XR traffic model from TR 38.838 with specific parameters for immersive gaming and UL-heavy video uploading scenarios.

#### Immersive Gaming Parameters (CG Traffic Model)

**Frame Generation and Data Rate Updates (Table 5.4.1-1 amendments):**
- **Data rate (R):** Added values of 100, 300, and 500 Mbps for immersive gaming (baseline: 30, 8 Mbps; optional: 45 Mbps)
- **Frame generation rate (F):** Added values of 90 and 120 fps for immersive gaming (baseline: 60 fps)
- **PDB:** 15 ms (baseline), with optional values of 10 or 30 ms

**Packet Size Distribution Updates (Table 5.1.1.1-1 amendments):**

For immersive gaming, using truncated Gaussian distribution:
- **Mean (M):** R×1e6 / F / 8 bytes
- **STD:** [25%] of M (compared to baseline 10.5% of M)
- **Max:** 300% of M (compared to baseline 150% of M)
- **Min:** 25% of M (compared to baseline 50% of M)

This represents significantly higher variability in packet sizes for immersive gaming compared to baseline XR.

#### UL-Heavy Video Uploading Parameters (AR UL Model 1)

**Updates to Table 5.5.2.1-1:**
- **Packet size:** Two candidates proposed:
  - 1st candidate: Follows clause 5.1.1.1 with STD/Min/Max = 10.5/50/150%
  - 2nd candidate: Follows clause 5.1.1.1 with STD/Min/Max = [25]/25/300%
- **Packet generation rate (F):** 15, 30 Hz (baseline: 60 Hz)
- **Data rate (R):** 20, 60, 100 Mbps (baseline: 10 Mbps; optional: 20 Mbps)
- **PDB:** 10, 15 ms (baseline: 30 ms; optional: 10, 15, or 60 ms)
- **Jitter:** Optional, follows description in clause 5.1.1.2

### Model-2: eXR Model with Haptics

This model introduces haptics traffic co-generated with XR traffic packets.

**Key Characteristics:**
- Haptics traffic defined as XR traffic packet generation with co-generated haptics packets
- **PDB for haptics packets:** Either 12 ms or 30 ms (selectable as traffic model parameter)

**Open Issues (FFS):**
- Generation methodology for multi-channel haptics packets
- Handling of silent periods in haptics transmission
- Haptics packet size determination
- Co-generation mechanism between haptics packets and XR traffic packets

## Action Requested

RAN1 requests SA4 to provide inputs on the proposed traffic models, particularly:
- Validation of the proposed parameter values for immersive gaming and UL video uploading
- Guidance on the FFS items for the haptics traffic model
- Any additional considerations from the service and application perspective

## Next RAN1 Meetings
- **RAN1 #124:** February 9-13, 2026, Gothenburg, Sweden
- **RAN1 #124bis:** April 13-17, 2026, Malta