NetMP – Multiplayer Reconnect & Player State Restoration
Restore disconnected players without losing their individual server-authoritative session state.
NetMP is a C++ plugin for Unreal Engine 5.3–5.8 that helps multiplayer developers handle player disconnections, reconnections, and client restarts.
Built for server-authoritative multiplayer games, NetMP supports dedicated servers, listen servers, and local split-screen players with independent identities.
Key Features
Player Reconnection: Restore previously registered players after connection loss.
Client Restart Recovery: Reconnect after completely restarting the game client using persisted credentials.
Local Split-Screen Support: Manage multiple LocalPlayers on the same client, each with an independent identity.
Server-Authoritative State Restoration: Restore previously captured player state without relying on client-reported values.
Secure Reconnect Credentials: Credential rotation, replay rejection, invalid-token protection, and Windows DPAPI-backed local credential storage.
ServerTravel Support: Preserve correct player identities and restoration behavior across supported travel scenarios.
Dedicated Server Support: Validated with packaged Windows and Linux dedicated servers.
Blueprint and C++ Integration: Includes example Blueprints, a demonstration map, and integration documentation.
Verified Compatibility
Unreal Engine 5.3, 5.4, 5.5, 5.6, 5.7, and 5.8.
Validated across 12 Windows/Linux dedicated-server and engine-version combinations.
Quality Assurance: 96 successful runtime test runs covering 2,604 checks, including reconnection, client restart, local split-screen, credential security, and ServerTravel scenarios.
Included
NetMP C++ plugin source code
Example Blueprint classes
Enhanced Input example assets
Demonstration map
Installation and integration documentation
Security guidance and known limitations
Important Limitations
NetMP is not a general-purpose network movement or prediction framework, matchmaking service, or account authentication backend.
Restoration uses server-held player state. Persisting player state across a full dedicated-server restart requires a separate server-side persistence solution.
NetMP is designed to integrate into your game's authoritative multiplayer architecture rather than replace it.
Dependency: Enhanced Input — Epic Games, included with Unreal Engine.