fail to run "run-laa-wifi-indoor-ftp.sh" when voiceEnable=1 with latest lbt version

[John Young]

I ran run-laa-wifi-indoor-ftp.sh. And it failed with an assert error " m_backoffSlots==0" in dcf-manager.cc. When voiceEnable=0,  it would work. And with a small base duration, it worked as well. However, when voiceEnabled=1, for laa +wifi lambda=0.5 ,the error appeared.

[Tom Henderson]

I made some changes to ns-3-dev to try to fix some of these DCF asserts
just prior to ns-3.26 release. However, I have not had time yet to
update the LAA repository's wifi code to that of ns-3.26.

I had previously observed this particular assert happening in the
context of bug 2493:
https://www.nsnam.org/bugzilla/show_bug.cgi?id=2493

You are discovering some parameter combinations that happen to trigger
this. Changing RngRun value for any given scenario might also trigger it.

- Tom

[John Young]

Ok.

在 2016年10月22日星期六 UTC+8下午11:23:49，Tom Henderson写道：

[John Young]

May I ask if there exists some other approaches to avoid the asserts except from trying different RngRun? It seems that the wifi part in ns3-lbt is somewhat different from ns-3-dev, so I can not simply copy it to ns-3-lbt. Right?

在 2016年10月22日星期六 UTC+8下午11:23:49，Tom Henderson写道：

On 10/22/2016 07:58 AM, John Young wrote:

[Tom Henderson]

On 10/25/2016 05:18 AM, John Young wrote:
> May I ask if there exists some other approaches to avoid the asserts
> except from trying different RngRun? It seems that the wifi part in
> ns3-lbt is somewhat different from ns-3-dev, so I can not simply copy it
> to ns-3-lbt. Right?

ns-3.26's wifi will need a patch. To see the extent of the patch, you
can refer to this changeset:
http://code.nsnam.org/laa/ns-3-lbt/rev/09e5eca5cc61

where I aligned src/wifi with changeset 12078 of ns-3-dev's src/wifi.

In general, what is needed is to compare those versions of src/wifi,
extract the diff, and reapply to the current src/wifi.

However, it is not that simple in practice, because 1) there may be API
changes that affect the wifi derivatives like mesh and wave, and 2)
there may be API changes like the recent fix to bug 231 that go across
many modules, and 3) there may be new issues that pop up during testing.

Biljana and I are discussing doing the ns-3-lbt upgrade to rebase on
ns-3.26 but we do not have an estimate yet of when we would complete.

- Tom

[John Young]

Ok, thanks.
在 2016年10月25日星期二 UTC+8下午9:08:19，Tom Henderson写道：