Bug 1011

Summary:	assert failed. file=../src/devices/wifi/dcf-manager.cc
Product:	ns-3	Reporter:	Alex <alejandro.espiga>
Component:	wifi	Assignee:	Nicola Baldo <nicola>
Status:	RESOLVED FIXED
Severity:	normal	CC:	nikkipui, ns-bugs, ruben, tomh, tommaso.pecorella
Priority:	P5
Version:	ns-3.7
Hardware:	PC
OS:	Linux
Attachments:	Test scenario for a record.

Description Alex 2010-10-21 07:25:19 UTC

I'm simulating a mesh network, the topology are 5 nodes on line, 90 meters apart. 
 
N0 <-----------> N1 <-----------> N2 <-----------> N3 <-----------> N4

I have set the wifi standard as WIFI_PHY_STANDARD_80211a and enable RTS/CTS.
I have 10 UDP OnOff applications installed from N1 to N0 and 10 other from N3 to N4. Packet size is 1024 Bytes. On node N2 I have an UDP client that send packet to N0 first, and then to N4.
With a datarate of 80 Kbps, per flow in applications on nodes N1 and N3, it works, but when I put datarate of 90 Kps I get the following error:
 
assert failed. file=../src/devices/wifi/dcf-manager.cc, line=699, cond="m_lastNavStart < Simulator::Now ()"
 
When I disable RTS/CTS this error disappears. 
Does anyone know why this error occurs? 

Thanks.

Comment 1 Daniel L. 2013-10-10 12:05:55 UTC

Created attachment 1678 [details]
Test scenario for a record.

Test scenario for a record.

Comment 2 Daniel L. 2013-10-10 12:08:46 UTC

I think changing the assert condition in DcfManager::NotifyNavStartNow from

NS_ASSERT (m_lastNavStart < Simulator::Now ());

to

NS_ASSERT (m_lastNavStart <= Simulator::Now ());

will fix this problem. The new condition is the same as in MacLow::NotifyNav.

Comment 3 Daniel L. 2013-10-10 12:16:15 UTC

changeset:   10211:1af765ed27c8