Why do different types of app have different start time settings in laa scenarioHelper?

[John Young]

I see in scenarioHelper, udp clientApps start with a jitter each, which means each udpClient starts at a different time. However, for ftp and tcp clients, all flows in the same operator network start at the same time. I  don't know why it is inconsistent...

[Tommaso Pecorella]

Perhaps the author forgot this bit or he didn't feel that it was important for the simulations.

T.

[Biljana Bojović]

Hi,

when selected "Udp" type of traffic, the simulation will be run with CBR application over UDP, and this means that there will be one flow per UE during the whole simulation. In this case, in order to avoid that packets are being sent at exactly the same time, it is necessary to add some randomness at start times of applications.

However, when option "Ftp" or "Tcp" is being selected, the simulation is run with "3GPP Ftp model 1" according to which file arrive with Poisson process, so in this case we do not need to introduce an additional randomness.

You can find more info about applications in the documentation: https://www.nsnam.org/~tomh/ns-3-lbt-documents/html/lbt-wifi-coexistence.html#applications

Hope this clarifies.

Best regards,
Biljana

[John Young]

Ok, thanks.

在 2016年10月24日星期一 UTC+8下午8:36:53，Biljana Bojović写道：