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Monday, December 20, 2010

Sushi For Your Gaming: Hamachi VPN for LAN multiplayer over the internet.

I've recently been playing some older games (Rainbow Six series) in co-op multi-player mode with some gaming buddies. An issue often faced when playing online, particularly with older games, is the availability of the various servers (log-in / authentication / etc.) from the publisher to enable this mode of play.

Sometimes, the servers are unavailable for maintenance or other reasons, sometimes they've been completely shut down when the game is at "end of life" by the publisher. What's a gamer to do that still enjoys playing with geographically dispersed friends for games that fall into these holes?

So long as the game incorporates a LAN multi-player aspect, this can be easily accomplished with the most excellent Hamachi VPN from LogMeIn.

In a nutshell, Hamachi provides a painless, zero-configuration (95% success) Virtual Private Network facility ideally suited to online gaming (unlike a typical VPN, Hamachi will pass broadcast and multi-cast traffic, vital for proper functioning of most LAN games.)

Non-commercial use is free, setup is quick and painless. The service provides a web-based interface to create networks, manage clients, and deploy customized client installers. The latter facility enables players with no technical expertise to easily become a member of your private gaming network without any Hamachi configuration - just a simple installation is required.

Mesh (all members can 'see' all other members), Hub-and-Spoke (Members are connected to hubs, hubs 'see' all members, members see only the hubs), and Gateway (members 'see' the entire physical network, and share its address space) networks are supported, Mesh being the most appropriate for most WAN based LAN gaming.

A really fantastic free service with very respectable performance and reliability, and security (encryption of data flow) when desired.

Its use is of course not limited to gaming: it makes a fine VPN for accessing your LAN while out on the road for general use.

A few caveats for gamers (these apply to the 'host' or originator of the network, and the clients / members):
  • Most games will use the 'first' LAN network adapter found on the machine for traffic. You must ensure that the Hamachi 'adapter' (actually a virtual adapter installed by Hamachi that is treated by the operating system as a real, physical adapter) is 'first' in the list. Failure to do so may result in an inability to connect the participating PCs together in the game (clients may not 'see' the server / host, etc.) You can adjust this by going to the advanced settings in your network connections control panel window (see image below), and using the arrows next to the connections window on the adapters and bindings tab. Move Hamachi to the top. You might need to reboot your machine for the changes to take effect.
  • Recent versions of Windows (7, and probably Vista though I've not verified this) have changed the behavior of broadcast traffic routing. This one had me head-scratching for a bit! Before, such traffic would be sent on the adapter used for the connection. In recent Windows, this order is ignored, and the adapter with the lowest interface metric will be used, regardless of its order in the adapters connections list. The result is symptoms similar to the adapter itself not being seen as 'first': clients will likely not see the server / host, or not be able to connect successfully. To remedy this, right-click on the Hamachi adapter in your network connections control panel window, select properties, double-click on the Internet Protocol Version 4 item, and click on the advanced button in the lower right of the dialog. Set the Interface Metric to 1 and reboot your machine (you can also try just disabling and re-enabling the Hamachi adapter in lieu of rebooting.) The default metric used by Hamachi of 9000 causes broadcast traffic to route over your 'real' NIC, causing connection issues for the games. Network internals savvy users may recognize there are other means to accomplish this end. Feel free to experiment - you won't permanently break anything.
Give it a look and a try. As long as a game supports LAN multi-player, you will always be able to enjoy it with friends in the cloud using this nifty tool.


1 comment:

  1. my kids used it to play WOW on a friends server, I understand now how it works. thanks.