ns3 queue in Traffic control layer

[Yuhang Dai]

Hi,

I'm using ns3.25 to do some queue stuff in mobile networks.

Compared with previous version, 3.25 has a traffic control (TC) module which applies queue discipline such as CoDel and RED before packets are sent to the device queue. However, I noticed that the packet accumulate in the device queue first rather than in the queue in TC layer. The device queue will be overflowed quickly if the rate of incoming traffic is faster than the outgoing traffic.

Hence, packets get dropped due to the overflow of device queue before any queue discipline works.

Any one has any idea about it? Is this the case in real Linux system or is it a bug in the design of ns3?


Best,
Yuhang

[Yang Wei]

Hi Yuhang:

     I am also struggling in the simulation of queue issues by NS3.

     I believe the traffic control module in NS3 3.25 is able to solve my problems, but I can still not figure out the solution.

     My email is yangwei...@gmail.com. Feel free to contact me to see if we can help each other to overcome the problems encountered.

     Best,

                       Wei 

[Tommaso Pecorella]

Hi,

TC had been introduced recently. Not all the NetDevices are TC-friendly (they must implement a sort of back pressure and stop the TC scheduler if their own queue is full).

I'm not sure if the Wi-Fi module is TC-friendly. For sure PointToPoint is.

Cheers,

T.

[Yang Wei]

Hi Tommaso Pecorella:

    Thank you very much for your suggestion.

    I do use the traffic control for PointToPoint simulation. 

    Let me try again.

    Best,

                    Wei

[Yuhang Dai]

Hi,

Can you give a detailed description about what you're struggling about?

Best,

Yuhang

--
Posting to this group should follow these guidelines https://www.nsnam.org/wiki/Ns-3-users-guidelines-for-posting
---
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/q8TCzJ4XXj8/unsubscribe.
To unsubscribe from this group and all its topics, send an email to ns-3-users+unsubscribe@googlegroups.com.
To post to this group, send email to ns-3-...@googlegroups.com.
Visit this group at https://groups.google.com/group/ns-3-users.
For more options, visit https://groups.google.com/d/optout.

[Yuhang Dai]

Hi Tommaso,

What do you mean by "back pressure"?

Best,

Yuhang

--

[Yang Wei]

Hi, please see my latest post:

 https://groups.google.com/forum/#!topic/ns-3-users/NoeKyWk2PfY

To unsubscribe from this group and all its topics, send an email to ns-3-users+...@googlegroups.com.

[Tommaso Pecorella]

The NetDevice must stop the queue from sending more packets if its internals are already full (and re-start it once it's possible to send more packets).

Check the PointToPointNetDevice.

Cheers,

T.

To unsubscribe from this group and all its topics, send an email to ns-3-users+...@googlegroups.com.

[Yuhang Dai]

Hi Tommaso,

You mean the TC layer should stop sending packets to the device queue if the device queue is alread full?

Best,

Yuhang

To unsubscribe from this group and all its topics, send an email to ns-3-users+unsubscribe@googlegroups.com.