# Summary: S4-260525 – Pseudo-CR on Annex for MOQT Session Setup and Media Delivery Models

**Source:** NTT | **Spec:** 3GPP TR 26.836 v0.1.1 | **WI:** FS_Q4RTC_MED | **For:** Agreement

## Purpose
Contributes informative annex content to TR 26.836 to support evaluation of Media over QUIC Transport (MOQT) for RTC application scenarios, as part of the FS_Q4RTC_MED study item.

## Changes Proposed

**References section update:**
- Updates reference [18] (draft-ietf-moq-transport) from draft-16 to draft-17 / March 2026 version.

**New Annex A (Informative): MOQT Session Setup and Media Delivery Models**

- **A.2 – MOQT Session:** Describes the MOQT session structure over native QUIC or WebTransport, covering use of unidirectional control streams (SETUP, GOAWAY), bidirectional request streams (SUBSCRIBE, PUBLISH, FETCH, etc.), and datagrams/streams for object delivery. Covers session setup (SETUP message exchange) and termination (CONNECTION_CLOSE for native QUIC; CLOSE_WEBTRANSPORT_SESSION for WebTransport).

- **A.3 – Media Delivery Models and Call Flows:** Defines two models:
  1. **E2E unidirectional delivery without Relay** – direct publisher-to-subscriber flow including namespace discovery (SUBSCRIBE_NAMESPACE, PUBLISH_NAMESPACE, or out-of-band), catalog track subscription (subscriber- or publisher-initiated via SUBSCRIBE/PUBLISH messages), media track subscription, and subscription termination (STOP_SENDING or PUBLISH_DONE).
  2. **Unidirectional delivery for multiple subscribers using Relay** – referenced but call flow detail not included in this contribution.

- Call flows assume use of **MOQT Streaming Format (MSF)** (draft-ietf-moq-msf) for catalog-based track discovery.

## Notes
- Contains minor editorial errors in the draft text (e.g., "PUPBLISH_OK", "publisehr", inconsistent step numbering) that would need correction before agreement.
- Relay model (A.3.3) is referenced but not yet populated in this contribution.