Free WAN Emulators?

ScottMan asks: "The company I work for is interested in WAN emulation software that does stuff like create false latency, random packet dropping, etc. After scouring every resource I know, I was able to find only one piece of software called The Cloud (at $4,000 a license) Does anyone know of ANY WAN emulation software that is GPL or similar?"

Will This Work?

[karma_policeman]

The LNBL Network Simulator, ns [lbl.gov], is a simulation tool developed by the Network Research Group at the Lawrence Berkeley National Laboratory. Ns is an extensible, easily configured and programmed event-driven simulation engine, with support for several flavors of TCP (include SACK, Tahoe and Reno) and router scheduling algorithms. This work derives from S. Keshav's REAL simulator.

There is also an ns version 2 [berkeley.edu] available.

I don't know if this is exactly what you're looking for, but it might help.

NIST Net

[LazyBoy]

Free. Good.
http://snad.ncsl.nist.gov/itg/nistnet/

-troy

Interface driver

[DeHackEd]

I seem to remember in an issue of Linux Magazine a while back (at least 5 months or more) they had a section on creating a virtual interface "driver" which redirected packets to a real interface and would cause random packet loss (either as a percentage or a network outage of half a second every 10 seconds or something like that). I don't have the magazines handy, but I would imagine you could find it somewhere on their web site [linux-mag.com] somewhere.

It was called "insane" and compiled as a kernel module.

Use "dummynet" in FreeBSD

[gillham]

It supports what you have asked for.
I've used it for just throttling and latency, but it supports packet dropping as well. Check it out.

Re:Use "dummynet" in FreeBSD

[icedivr]

Dummynet is great for this sort of application. I set up a small FreeBSD box at work with 5 IPs. I then configured a different set of pipes for each ip, 28.8, 33.6, 56, ISDN and DSL. I also configured different latencies and a small amount of packet loss. Now, if our developers want to simulate a low-speed connection, they configure their browswer to use the appropriate IP, where they connect to squid, and then to the appropriate devel server.

FreeBSD dummynet

[peril]

I'm pretty sure the FreeBSD dummynet device can do this, I haven't configured it, but in the right kind of combination, (serial ethernet Token Ring ATM) interface/tunnel mixes, you could simulate PPP ,ring and broadcast technologies for WAN or LAN....
http://www.iet.unipi.it/~luigi/ip_dummynet/

FreeBSD's dummynet

[Delta]

FreeBSD has a feature called dummynet. It allows you to configure network pipes which allows you to limit bandwith, add latency and even packet loss. It's quite a nicely designed feature. You use the ipfw tool to configure it, and you use firewall rules to send traffic into the pipes, so you can controll which content you want to limit.

You can use it on the host you want to use, or you can easily build a FreeBSD gateway/router box and set things up there. More in formation is available at www.freebsd.org.