> ## Documentation Index
> Fetch the complete documentation index at: https://devdocs.xbox.com/llms.txt
> Use this file to discover all available pages before exploring further.

# XR-067 Maintaining Multiplayer Session State

> Multiplayer sessions must maintain accurate state through joins, leaves, host migration, network glitches, and platform events without desyncing or crashing.

## Intent

A multiplayer session's state — who's in, what roles, what mode, what map — must stay accurate throughout the session's lifecycle. If state gets desynced or corrupted, joining players see wrong information and existing players are dropped into wrong contexts. XR-067 requires titles maintain session state through every reasonable perturbation.

## Applies to

Every title with multiplayer session state (MPSD or modern equivalent).

## Requirement

Your title **MUST**:

* Keep the **MPSD session state** in sync with the runtime session on every state transition (member join, member leave, role change, mode change, host migration).
* Handle **host migration** correctly when the host disconnects — elect a new host, transfer authoritative state, notify remaining members.
* Handle **member disconnect** — remove the departed member from session state, notify remaining members, adjust joinability if the session is now not full.
* Handle **network glitches** — transient network loss on the host must not tear down the session if recovery is quick.
* Handle **platform events** — sign-out, Quick Resume, controller change — without corrupting the session for other members.
* **Persist session identity** correctly through host migration so join-from-presence still finds the migrated session.
* Clean up sessions when they naturally end (all members leave, game completes) so the session doesn't ghost in MPSD.

Your title **MUST NOT**:

* Show session state inconsistently across members.
* Allow a stale MPSD session to persist after the runtime session has ended.
* Drop all remaining members when the host disconnects.
* Fabricate members in the session state that aren't actually connected.

## Tested scenarios

* Host a 4-player session. Have the host disconnect (network pull). Verify host migration; verify remaining 3 members continue.
* Have a non-host member disconnect. Verify graceful removal from state.
* Rapidly join / leave the session. Verify session state stays consistent.
* Change game mode mid-lobby. Verify state propagates to all members.
* Sign out mid-session. Verify session state updates for the remaining members.

## Best practices

* **Design an authoritative host** or **arbitrated session** so there's a single source of truth on session state.
* **Use MPSD writes carefully** — rate-limit them to avoid throttling under [XR-132](/publishing/certification/xr/xr-132).
* **Reconcile after network glitches** — on reconnect, re-read MPSD state and diff against runtime.
* **Timebound host-migration** — if no new host is elected in a bounded time, tear down cleanly rather than hanging.

## Related XRs

* [XR-064](/publishing/certification/xr/xr-064) — Joinable sessions.
* [XR-070](/publishing/certification/fma/xr-070) — Friends list.
* [XR-074](/publishing/certification/xr/xr-074) — Loss of connectivity.
* [XR-115](/publishing/certification/xr/xr-115) — Adding / removing users during gameplay.
* [XR-124](/publishing/certification/fma/xr-124) — Game invitations.
* [XR-132](/publishing/certification/xr/xr-132) — Service access limits.

## If your title fails XR-067

See [FMA: XR-067 Maintaining Multiplayer Session State](/publishing/certification/fma/xr-067).

## Related

* [XBOX services](/services/xbox-services/index)
* [Top failing tests](/publishing/certification/xr-top-failing)
* [XBOX requirements](/publishing/certification/xbox-requirements)


## Related topics

- [XBOX Requirement test cases for PC and mobile games](/publishing/certification/pc-policy-tests.md)
- [PC and mobile certification requirements and top failures](/publishing/certification/pc-certification.md)
- [XBOX Certification overview](/publishing/certification/overview.md)
- [FMA: XR-067 Maintaining Multiplayer Session State](/publishing/certification/fma/xr-067.md)
- [XR-124 Game Invitations](/publishing/certification/xr/xr-124.md)