ON/OFF periods for Wi-Fi

[m.alh...@gmail.com]

Hello there,

I an trying to run laa-wifi-indoor scenario example by setting ConfigA=LTE and ConfigB=Wifi, i need to know the duration for the NO and OFF in seconds for the Wifi packets. How can i get that?. in fact i need to know these instances such that i can know the CDF for the NO and OFF states for WiFi.

Regards,

 

[Tommaso Pecorella]

Sorry... but Wi-Fi doesn't have ON or OFF periods. It just flows its standard rules for backoff periods upon sensing a busy channel.

T.

[m.alh...@gmail.com]

Hello Tommaso,

I know that there are no ON or OFF periods in Wi-Fi, what i mean that in Wi-Fi transmissions the Wi-Fi does not use the channel the whole time. Thus, can i know the time that the Wi-Fi use the channel and the time that it does not use the channel.

Imagine that even we are using just the Wi-Fi module (we have just wifi nodes), can i know in ns3 the time duration that the WiFi uses the channel?.

Regards.

[Tommaso Pecorella]

Define "uses the channel" - and try to be specific. Only THEN you'll be able to find your answer.

T.

[m.alh...@gmail.com]

Hello Dear,

Suppose that we have a some WiFi nodes connected to an AP in 5 GHz band. As we know that the transmission here follows the backoff and the contention window. Surely, the Wifi does not use the channel the whole time, wifi nodes or AP use the channel for some durations to transmit their own packets, i need to know these durations that the wifi nodes and the AP use the channel. Because i have an idea to exploit the LAA in the durations that the wifi does not use the channel. 

[Tommaso Pecorella]

Have you ever considered that a node knows about itself more stuff than an external node can know ?

You can measure the time a node is using the channel by looking at its internal state transitions (there's a trace for that), but an external node can NOT access that. Be my guest in measuring it (but be my guest in making sense out of different nodes states), but remember that a LTE node will not be able to access that info. Moreover... well, one thing is what a node does, another thing is what the channel is. There's something called channel propagation and attenuation...

That's the problem of channel sensing.

T.

[m.alh...@gmail.com]

Thank you for your reply.

Where can i find that trace to measure the time that a node is using the channel (internal state transitions)?

Regards. 

[Konstantinos]

All available trace sources are listed here https://www.nsnam.org/docs/doxygen/_trace_source_list.html

What you are looking for is the State trace source from WifiPhyStateHelper class which monitors the transition between the states (idle, Tx, Rx, cca_busy, etc)

Regards

K

[Khairunnisa nisa]

Hi All

i want to simulate offloading traffic from cellular to wifi with andsf. can i get some script for andsf on ns3?