Bug 2729

Summary:	ARP are not sent when queues are full.
Product:	ns-3	Reporter:	Tommaso Pecorella <tommaso.pecorella>
Component:	internet	Assignee:	Tommaso Pecorella <tommaso.pecorella>
Status:	NEEDINFO ---
Severity:	minor	CC:	ns-bugs
Priority:	P3
Version:	ns-3-dev
Hardware:	All
OS:	All
Attachments:	test script

Description Tommaso Pecorella 2017-04-22 07:36:23 UTC

Created attachment 2836 [details]
test script

For real this is a Wi-Fi / Internet pairing issue.

It has been raised here:
https://groups.google.com/forum/#!topic/ns-3-users/saEH63E3XmM
but the problem description is misleading, the number of STAs is not important.

The real issue is this: when a node is congested by its own flows, the IP control packets (ARP, NDISC, etc.) are not sent (or replied to).

The solution could be to add a priority to these packets, but the compatibility with other NetDevices have to be kept.

Comment 1 sebastien.deronne 2017-05-01 15:19:23 UTC

Is this really a wifi issue? I do not have impression something will be change in wifi code for this. To be checked by Stefano as well.

Comment 2 sebastien.deronne 2017-05-15 13:00:17 UTC

I think this is not really a bug.
As you said on the user forum, UDP isn't a fair protocol and the first incoming packets will win the access.

This can only be solved by changing how the queues behave (I know in ns-2 there were some various queue management policies that could be configured).
Stefano, what do you suggest here? Should it be assigned to wifi or to network module?