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If you use Linux you can use tc - the traffic control program. It should be standard in your distro. For example, to set the upload maximum speed (in this case 100 kbit per second): $ sudo tc qdisc add dev eth1 root tbf rate 100kbit latency 600ms burst 1540 to set the download maximum speed (in this case 500 kbit per second): $ sudo tc qdisc add dev eth0 ...


http://communities.vmware.com/blogs/Knorrhane/2008/01/23/how-to-simulate-wan-connections-in-your-own-test-lab-for-free VMware Workstation to simulate the network - $189 Netlimiter 2 Pro to slow down the network - $29.95 Tmurgent to simulate packet loss (and latency) - free!


Hmmm... hadn't heard of Smokeping. I use something pretty similar to it (almost identical), though looks like MTR has more field categories for Packet delivery and Jitter statistics.


A quick back-of-my hand calculation gives the following data: 100 mbit bit rate is 100 000 000 bits/second (network, so not 1024) A full length ethernet frame is 1518 bytes, 12 144 bits. Transfer of a full packet takes 12144/100000000 seconds, around 0.12 ms. A minimum length ethernet frame is 64 byes, 512 bits. Transfer of a minimal packet takes ...


DummyNet is a free piece of software that can be used to simulate various network conditions. If you have a spare machine, install FreeBSD and DummyNet, and put it inline between your client and server. You can then tweak DummyNet to vary the latency, jitter and loss that you experience. EDIT: just re-read the question and realised you don't own your ...


Jitter might be part of calculating the quality of service. This is not limited to VOIP but also for streaming video/audio for instance. You could basically use jitter (and of course other parameters) to get an early warning of worsening service quality. If you compare the measured jitter with the current server load, it might be possible to indicate even ...


The best way to do this is probably by using the netem kernel module. See here for more detail. It will allow you to do any and all of the above and then some. This has been part of the linux kernel since 2.6, so should be available in just about any distro by now.


It seems that both PFSense and m0n0wall support dummynet traffic shaper. dummynet is a tool originally designed for testing networking protocols, and since then used for a variety of applications including bandwidth management. It simulates/enforces queue and bandwidth limitations, delays, packet losses, and multipath effects.

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