[ns] [bug] multiple parallel 802.11 channels problem

[speicher at informatik.uni-rostock.de]

[Bug Report]

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Category:  Run Time - Segmentation Fault
Package:   ns 2.27
OS:        Linux 2.6.5-1.358
Environment Variables:
LD_LIBRARY_PATH=/home/speicher/ns-allinone-2.27/otcl-1.8:/home/speicher/ns-allinone-2.27/lib
TCL_LIBRARY=/home/speicher/ns-allinone-2.27/tcl8.4.5/library
TK_LIBRARY=


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Description:

Description of Problem:
I am experiencing problems when trying to set up multiple parallel 
802.11b channels in NS-2.

The problem can be reproduced with the example file wireless-mitf.tcl. 
As suggested in the file, when I simply uncomment the marked lines to 
configure node 1 to a different channel than node 0 and run the example 
it leads to a segmentation fault. This also happens if I comment out the 
traffic flow which is configured in the example between the nodes (which 
obviously shouldn't work now anyway - since the nodes are on different channels). Debugging shows that the segmentation fault happens in WirelessChannel::getAffectedNodes().

What I am actually trying to do is run several 802.11 ad hoc LANs on 
different channels in parallel.

How Easily Reproducible:
(e.g. every time, intermittent, once only, etc.)
Every time

Steps to Reproduce:
1. Uncomment lines 115 and 116 in tcl/ex/wireless-mitf.tcl
2. run ns wireless-mitf.tcl

Actual Results:
Segmentation fault

Expected Results:
Shouldn't crash and (if it doesn't crash) no data should be exchanged between nodes (since they are on different channels).