Multiplayer Configuration

  • The article about the basic setup of UA multiplayer after the deprecation of the official MS Zone, including network configuration settings and relevant information for hosting multiplayer games.

    1 Summary

    This article explains the basic setup methods for UA multiplayer after the deprecation of the official MS Zone. Gameplay tips, level guides, and other custom topics such as modified multiplayer contents are not included in this article.


    This article does not apply to OpenUA. Which employs different and refactored algorithms and protocols for its multiplayer layers. The multiplayer aspect of OpenUA will be covered in another article.


    2 Information

    2.1 Basic Overview

    Urban Assault uses DirectPlay 7 for multiplayer. It is old Microsoft technology and can be tricky to set up properly.


    All players should use the same game executable - for example, UA.exe (Original UA), Ua_xp.exe (MD Expansion) or ua_trial.exe (Demo). Otherwise they may be unable to connect due to a version mismatch. The version check can be disabled via Nucleus.ini config file, but it is highly recommended to NOT do so since it may cause numerous issues.


    If players have different game data contents, a warning message appears. Any type of unofficial, script-based custom game data modification contents can cause this problem, and at a high chance it also indicates cheating. Therefore, it is imperative to maintain the same data-set between the match players before starting the game.


    If you are playing with a stranger and this error is triggered in the game, do not play with them as they may be potentially cheating.


    OpenUA now supports basic multiplayer functionality, but the algorithms and protocols are quite different from the original UA methods. It will be covered in a separate article later.


    2.2 Compact Disc Requirements

    The players need one compact disc for up to three players. The players need at least two compact discs for four players. Anyone playing a multiplayer game without a compact disc, must have installed a Complete installation.


    2.3 Connecting manually over internet (TCP/IP)

    This method is available in the multiplayer menu. It is the most basic and probably the most reliable way to set up a multiplayer game, but it requires the largest amount of configuration. The joining players must know the IP address of the host player to connect.


    The following ports must be available for incoming connections in Urban Assault:


    * 47624 - DirectPlay 7 initial connection


    * 2300-2400 - DirectPlay data connections. The entire range should be available.


    Due to the nature of DirectPlay, all players must have these ports forwarded, not just the host. If these ports can't be used for incoming connections (firewall inaccessible to the user, carrier-grade NAT etc.), then other methods must be used for multiplayer.


    2.4 Using GameRanger

    GameRanger is a software that allows easy set-up of game rooms for many multiplayer games, including UA. It automates the connection procedure and it can often perform NAT traversal which reduces the amount of configuration needed. However, if you are behind a NAT router, it's still recommended to forward port 16000 for GameRanger.


    GameRanger does not support the Metropolis Dawn -env parameter, but a specifically designed and verified multiplayer mod is sometimes used to import MD content without changing gameplay.


    Other disadvantages of GameRanger include the potential unreliability of the initial connection (reported by many people) and the amount of advertisements in the software itself. Also, the connection quality in general is reported to be unstable compared to the native TCP/IP connection method of UA.


    2.5 Using Hamachi

    Hamachi is a program that can set up a simple virtual network for games. It has been widely used to play UA for a long time.


    2.6 Connecting manually over serial

    Multiplayer over a serial connection is mostly obsolete but might be fun as a retro project. It's usually available in the multiplayer menu.


    Two local computers with a serial port and a null-modem cable are required.


    If a real serial port is not available, a USB → RS-232 adapter should work as well. However, the DirectPlay serial interface seems to support ports COM1…COM4 only. If such an adapter registers itself as something else, such as COM10, you have to manually change the port number via Windows Device Manager.


    2.7 Connecting manually over dialup

    Dialup technology is mostly obsolete. It's usually available in the multiplayer menu.


    Only levels with the dialup tag ('slow_connection' parameter set) can be played over a dialup connection.


    2.8 Connecting manually over IPX

    According to the official Help files and documents, UA supports IPX connection for multiplayer. However, the IPX protocol is mostly obsolete, and on modern systems, this option is usually not visible in the multiplayer menu at all.


    3 OpenUA

    OpenUA is a clean-room, open-source re-implementation project of the original Urban Assault engine. The multiplayer layers of OpenUA are currently under development and have numerous differences between the original multiplayer layers of the original UA including the general interface and protocols.


    As referenced in the summary at the top of this article, the multiplayer aspect and functionality of the OpenUA is covered in the OpenUA (UA:Source) article.


    4 Technical Assistance

    Should you have any other questions related to the topic, feel free to ask at the community forums.

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