Help with Error models

[Anumit Sasidharan]

Hi,

I'm rather new to NS3, and was going through examples/tutorial/sixth.cc

In the example sixth.cc, an error rate of 0.00001 is applied:

  Ptr<RateErrorModel> em = CreateObject<RateErrorModel> ();

  em->SetAttribute ("ErrorRate", DoubleValue (0.00001));

  devices.Get (1)->SetAttribute ("ReceiveErrorModel", PointerValue (em));

 

So, what I would like to do is to recreate the same example, but want different error rates for different time-slices. That is, for the first 5 seconds, I want an error rate of 0.00001, the next 5 seconds I want 0.00002, the next 5 - 100% error rate(all packets are dropped), and the last 5 seconds again with 0.00001.

The problem is that the error model is attached to the device itself, so it remains the same throughout the run-time of the application.

Do you have any suggestions on how I can achieve this? Any other classes or modules that I can use? Or if you can point me to any other examples which are doing something similar?

Any help/hints will be really appreciated. Thanks!

[Tommaso Pecorella]

Simulator::Schedule (Seconds (5), &RateErrorModel::SetRate, em, 0.00002);
Simulator::Schedule (Seconds (10), &RateErrorModel::SetRate, em, 1);
Simulator::Schedule (Seconds (15), &RateErrorModel::SetRate, em, 0.00001);

It's drycoding... I may have done any stupid error or typo.

Cheers,

T.

[Anumit Sasidharan]

Wow. I hadn't expected it to be this simple. Worked beautifully. Thanks a ton.

[Weitao Dong]

Hello,

I am curious that Could I add some random packet loss on it, not like his 5 seconds and 10 seconds. All the time are in the random packet loss between for example 5 to 10%. Is it possible? Thank you!

[Tommaso Pecorella]

The error rate does set the error probability. Packets are not dropped in a deterministic way (well, not in this model).

What is fixed is when (the time) the channel is switching the drop probability.

T.