How can I selectively increase latency? E.g. throttle games

Basically, I want networked games to run poorly on a network, but I want everything else to run smoothly.

I would also appreciate advice on blocking games in general.

As far as I can tell, there's a few ways to completely prevent an internet game from running:

Blocking entirely via DNS configuration (e.g. hosts file), or router DNS configuration
Blocking entirely via a separate DNS server
Blocking the application, by uninstalling or some kind of access control
Blocking the application by automatically killing the process every once in a while
Blocking the application by corrupting files periodically

However, I would like a more subtle way to block a program. Something that either:

Increases latency (would this be doable through some kind of QoS like what DD-WRT offers?)
Increases latency by using a special routing configuration for specific target IPs
Throttle other systems resources, such as memory, IO, or CPU
Screw around with keyboard configurations when a game is launched

I would like this to work on MacOSX and Windows, but Linux would be great too.

FYI I don't have a kid, but I was brainstorming with some friends and parents.

Arcymag

Posted 2012-09-27T06:23:38.760

Reputation: 143

Quick & very Dirty: Tomato QoS on home router which restricts all UDP traffic to very low bandwith (exceptions for skype and DNS lookups) – cloneman – 2012-10-03T01:47:52.863

Answers

From http://hints.macworld.com/article.php?story=20080119112509736

Advanced OS X users know that Darwin comes with ipfw, which can be used to set up a custom firewall. This same service however can be used to also limit bandwidth on specific ports.

Example: sudo ipfw pipe 1 config bw 15KByte/s creates a pipe that only allows up to 15KB/s to go through.

Then: sudo ipfw add 1 pipe 1 src-port 80 will attach that pipe to the outgoing traffic on port 80, effectively limiting the outgoing traffic of the web server. sudo ipfw delete 1 will remove the pipe from the port.

sourcedelica

Posted 2012-09-27T06:23:38.760

Reputation: 136

Useful to know. thanks! If you knew of a way to do something similar on windows (or a free program to do that), it'd pretty much wrap it up. – Arcymag – 2012-09-28T20:43:52.763

Per David's comment ipfw32 is a port of ipfw to Windows, so you shoudl be about to get it to work there. – sourcedelica – 2012-09-28T23:42:40.580

There is software called wanem wich can incease lattency(delay), packet loss and bandwith for specific ip, and port in network. It comes as live CD running linux, but you can run it as virtual machine from some other computer.
All you have to do is proper routing and setting IP-s on network if you have such skills and running this 24/7

ralu

Posted 2012-09-27T06:23:38.760

Reputation: 65

Interesting. I'd prefer if it didn't require a separate machine running 24/7, although it would be okay if it could run embedded on an existing home router. It looks like it also runs in a VM, but that might be pretty conspicuous under certain circumstances. – Arcymag – 2012-09-27T06:39:03.723

YOu probbaly could, I was using this to test how my server performs on loss of data and packets drops and did not went into used tools.

You might try then netem http://www.linuxfoundation.org/collaborate/workgroups/networking/netem . It is by default in kernel 2.6

– ralu – 2012-09-27T06:46:09.037

The IPFIREWALL ( IPFW ) is a FreeBSD sponsored firewall software application authored and maintained by FreeBSD volunteer staff members. Now works on Windows XP/Vista/7!

Please extract to D:\binary\ or change the syntax in wall.cmd

ipfw32

David McGowan

Posted 2012-09-27T06:23:38.760

Reputation: 462