All,
Some colleagues and I are trying to simulate two separate ad hoc networks
running simultaneously in the same geographic area in order to determine the
negative effects of their uncoordinated interaction. The two networks have
different wireless propagation models, which seems to be allowed by ns. We
are defining the groups of nodes as follows:
. . .
set val(chan) Channel/WirelessChannel ;# channel type
set val(prop2) Propagation/TwoRayGround ;# radio-propagation model
set val(prop1) Propagation/OtherPropModel ;# new propagation model
set val(netif) Phy/WirelessPhy ;# network interface type
set val(mac) Mac/802_11 ;# MAC type
set val(rp1) AODV ;# AODV
set val(rp2) OLSR ;# OLSR
. . .
$ns_ node-config -adhocRouting $val(rp1) \
-macType $val(mac) \
-propType $val(prop1) \
-llType $val(ll) \
-macType $val(mac) \
-ifqType $val(ifq) \
-ifqLen $val(ifqlen) \
-antType $val(ant) \
-propType $val(prop1) \
-phyType $val(netif) \
-channelType $val(chan) \
-topoInstance $topo \
for {set i $val(nn1)} {$i < $val(nn2) } {incr i} {
set node_($i) [$ns_ node]
}
. . .
$ns_ node-config -adhocRouting $val(rp2) \
-macType $val(mac) \
-propType $val(prop2) \
-llType $val(ll) \
-macType $val(mac) \
-ifqType $val(ifq) \
-ifqLen $val(ifqlen) \
-antType $val(ant) \
-propType $val(prop1) \
-phyType $val(netif) \
-channelType $val(chan) \
-topoInstance $topo \
for {set i $val(nn2)} {$i < $val(nn) } {incr i} {
set node_($i) [$ns_ node]
}
. . .
When we do this, we get two separate groups of nodes using different ad hoc
routing protocols, but they both use the same radio propagation model, even
when we explicitly define them to have different propagation models (prop1
and prop2). As it turns out, whichever propagation model is defined for the
first set of nodes is the one that gets used by both groups.
I've done some digging in the ns source, but not enough to figure out whey
this is happening. Any advice is appreciated.
Regards,
-Dave
