Assert Failed LTE simulation error

[Bektaş Şahin]

Hey all, I am trying to run a simulation with ns3 that includes LTE and on/off application. Now when I run, it compiles normally however I get an error like this after it finishes building;

assert failed. cond="uid != 0", msg="Assert in TypeId::LookupByName: Constant:1 not found", file=../src/core/model/type-id.cc, line=539
terminate called without an active exception

I also attached my code file as it might be helpful to see what I did wrong. Thanks

[Konstantinos]

Hi,

Just read the error you are getting: "Constant:1 not found".

Where have you used this in your code? 

        onoff.SetAttribute("OnTime", StringValue("Constant:1"));
        onoff.SetAttribute("OffTime", StringValue("Constant:0"));

So, it looks like this is not the correct way of setting the attribute On/OffTime.

How can you find out how? (a) look at the documentation, (b) ask the mailing list for that problem, not to debug your code!

http://www.nsnam.org/doxygen/classns3_1_1_on_off_application.html

OnTime: A RandomVariableStream used to pick the duration of the 'On' state.
Set with class: ns3::PointerValue
Underlying type: ns3::Ptr< ns3::RandomVariableStream >
Initial value: ns3::ConstantRandomVariable[Constant=1.0]
Flags: construct write read
OffTime: A RandomVariableStream used to pick the duration of the 'Off' state.
Set with class: ns3::PointerValue
Underlying type: ns3::Ptr< ns3::RandomVariableStream >
Initial value: ns3::ConstantRandomVariable[Constant=1.0]
Flags: construct write read

[Bektaş Şahin]

Hey there again Konstantinos;

I fixed the issue regarding OnOff application thanks to your post. Now it compiles and runs fine however the FlowMonitor results are weird, like I get same results for every node I have and it is incorrect(i.e duration is -2). I thought maybe it was because OnOff and switched to Udp and the same incorrect results persisted. What I am trying to achieve is some performance parameters in a scenario of one ENodeB and 10-15 nodes placed around it. An example of the result is below; I also attached my code with UDP application.


Flow ID            : 2 ; 10.1.1.3 -----> 10.1.1.1
Duration        : -2
Last Received Packet    : 0 Seconds
Throughput: -0 Mbps

Would appreciate if you can help me clear this.

Bektaş

[Konstantinos]

There is no problem with your code. The only problem is the way you interpret the output.

You calculate the duration as (Time_Last_Rx - Time_First_Tx) 

The first call of the method (ThroughputMonitor) is at t=3sec, and the client has started at t=2sec. 

So, the Time_First_Tx = 2.

From the output you get that Rx packets = 0, so Time_Last_Rx = 0 since you haven't received any packet.

Finally, duration = 0 - 2 = -2

So the output is correct!

There are logical problems though. I see that you have installed the server on the eNBs. I do not think that this is correct. You can have uplink/downlink from a remote host.

I would recommend to read the documentation for LTE module one more time to understand the architecture.  

[Bektaş Şahin]

Thanks again, so if I used OnOff application instead of Udp, in which I dont need to install server on enb at all, will it be any different granted that I changed the time parameters? I will try it with a remote host uplink/downlink than I will need an application (like OnOff) to analyze throughput etc right? Anyway I will reread the documentation. Thanks for your time.

Bektaş

--
You received this message because you are subscribed to a topic in the Google Groups "ns-3-users" group.
To unsubscribe from this topic, visit https://groups.google.com/d/topic/ns-3-users/sThL8dYVihs/unsubscribe.
To unsubscribe from this group and all its topics, send an email to ns-3-users+...@googlegroups.com.
To post to this group, send email to ns-3-...@googlegroups.com.
Visit this group at http://groups.google.com/group/ns-3-users.
For more options, visit https://groups.google.com/groups/opt_out.

[Bektaş Şahin]

Hey Konstantinos

I modified the code to include a remotehost that I can install the UDP server on and also I removed flowmonitor on enB which was not supposed to be there I presume. Anyway now I am trying to build it with the code;

./waf --command-template="%s --ns3::ConfigStore::Filename=input-defaults.txt --ns3::ConfigStore::Mode=Load --ns3::ConfigStore::FileFormat=RawText" --run scratch/lena_trial

however waf compiles lena-simple-epc in the lte example folder which I compiled earlier. Thus giving me an error all the time and I have no clue how this can happen. I attached a screenshot and a newer version of the code, is that some kind of a bug that I need to restart something? Because I already tried reconfiguring waf and enabling examples tests etc..

[Konstantinos]

You have to correct all compile errors from the files that are build in order to run a scenario.

These files include ALL files in scratch and the modules that you have configured (examples/tests etc).

So if you modified something in the lena-simple-epc code and it is not compiling (from the errors it looks like you haven't included the FlowMonitor module header), then you can not run another program. 

[Haftu Hagos]

hey Bektas Sahn;

can you please share me on how to solve the on/off application problem?
here is the error message.

"assert failed. cond="uid != 0", msg="Assert in TypeId::LookupByName: Constant:1 not found", file=../src/core/model/type-id.cc, line=539
terminate called without an active exception"

thanks !!!

[Bektaş Şahin]

Hey Haftu

I cant know without looking at your code but I believe it is a similar one to the problem I had. I think you are defining the OnTime and OffTime wrongly. Try these instead and see if it works for you;

      onoff.SetAttribute ("OnTime", StringValue("ns3::ConstantRandomVariable[Constant=2]"));
      onoff.SetAttribute ("OffTime", StringValue("ns3::ConstantRandomVariable[Constant=0]"));

Cheers
Bektaş

[Haftu Hagos]

Hey Bektas Sahin;

Thanks a lot for your quick reply and your genius answer. Your answer
fixes my problem.

thanks again.

shall I ask you more if you have good understands on LTE networks? I
am trying to work on it but i haven't even the basic understandings of
it.

cheers!!!

> --
> You received this message because you are subscribed to a topic in the
> Google Groups "ns-3-users" group.
> To unsubscribe from this topic, visit
> https://groups.google.com/d/topic/ns-3-users/sThL8dYVihs/unsubscribe.
> To unsubscribe from this group and all its topics, send an email to
> ns-3-users+...@googlegroups.com.
> To post to this group, send email to ns-3-...@googlegroups.com.
> Visit this group at http://groups.google.com/group/ns-3-users.

> For more options, visit https://groups.google.com/d/optout.
>

[Bektaş Şahin]

Hey Haftu

Sure you can ask me, but I am merely a new user. You would be better off if you asked the whole group, than again I will try to help as well. 

Regards

Bektas