《NS网络模拟和协议仿真》书上的源代码如下：
#无线节点参数
set val(chan) Channel/WirelessChannel ;# channel type 信道类型：无线信道
set val(prop) Propagation/TwoRayGround ;# radio-propagation model 信道模型：TwoRayGround
set val(netif) Phy/WirelessPhy ;# network interface type 无线物理层
set val(mac) Mac/802_11 ;# MAC type MAC层协议
set val(ifq) Queue/DropTail/PriQueue ;# interface queue type
set val(ll) LL ;# link layer type
set val(ant) Antenna/OmniAntenna ;# antenna model
set val(ifqlen) 50 ;# max packet in ifq
set val(rp) DSDV ;#路由协议
set val(nn) 4 ;#节点数目
set val(x) 600 ;
set val(y) 600 ;
set val(stop) 10.0 ;# time of simulation end
建立一个simulator实例
set ns [new Simulator]
#设定分层路由地址
$ns node-config -addressType hierarchical
AddrParams set domain_num_ 2 ;# 2个网络
lappend cluster_num 1 1 ;# 每个网络一个子网
AddrParams set cluster_num_ $cluster_num
lappend eilastlevel 1 3 ;# 2个子网的节点数目为1和3
AddrParams set nodes_num_ $eilastlevel
puts "Configuration of hierarchical addressing done"
#$ns use-newtrace
#设置trace
set tracefd [open wired_wireless2.tr w]
set namtrace [open wired_wireless2.nam w]
$ns trace-all $tracefd
$ns namtrace-all-wireless $namtrace $val(x) $val(y)
#建立topology对象
set topo [new Topography]
$topo load_flatgrid $val(x) $val(y)
#创建god
create-god $val(nn)
set sinkNode [$ns node 0.0.0]
$sinkNode set X_ 500
$sinkNode set Y_ 300
$sinkNode set Z_ 0
$ns initial_node_pos $sinkNode 60
set chan_1_ [new $val(chan)]
#无线节点配置
$ns node-config -wiredRouting ON \
-adhocRouting $val(rp) \
-llType $val(ll) \
-macType $val(mac) \
-ifqType $val(ifq) \
-ifqLen $val(ifqlen) \
-antType $val(ant) \
-propType $val(prop) \
-phyType $val(netif) \
-channel $chan_1_ \
-topoInstance $topo \
-agentTrace ON \
-routerTrace ON \
-macTrace ON \
-movementTrace OFF
#新建BS节点
set bs(0) [$ns node 1.0.0]
$bs(0) random-motion 0
#节点标签与初始位置设定
$bs(0) set X_ 200.0
$bs(0) set Y_ 300.0
$bs(0) set Z_ 0.0
$ns initial_node_pos $bs(0) 60
#定义节点间的链路
$ns duplex-link $sinkNode $bs(0) 10Mb 1ms DropTail
$ns duplex-link-op $sinkNode $bs(0) orient left
#定义链路的队列长度
#$ns queue-limit $bs(0) $sinkNode 10
#监视链路的队列
#$ns duplex-link-op $bs(0) $sinkNode queuePos 0.5
$ns node-config -wiredRouting OFF \
-macType Mac/802_11
#新建SS节点
set ss(0) [$ns node 1.0.1]
$ss(0) base-station [AddrParams addr2id [$bs(0) node-addr]]
$ss(0) set X_ 50.0
$ss(0) set Y_ 450.0
$ss(0) set Z_ 0.0
$ns initial_node_pos $ss(0) 60
set ss(1) [$ns node 1.0.2]
$ss(1) base-station [AddrParams addr2id [$bs(0) node-addr]]
$ss(1) set X_ 50.0
$ss(1) set Y_ 150.0
$ss(1) set Z_ 0.0
$ns initial_node_pos $ss(1) 60
set udp0 [new Agent/UDP]
$ns attach-agent $ss(0) $udp0
set null0 [new Agent/Null]
$ns attach-agent $sinkNode $null0
$ns connect $udp0 $null0
set ugs0 [new Application/Traffic/UGS]
$ugs0 attach-agent $udp0
set udp1 [new Agent/UDP]
$ns attach-agent $sinkNode $udp1
set null1 [new Agent/Null]
$ns attach-agent $ss(1) $null1
$ns connect $udp1 $null1
set ugs1 [new Application/Traffic/UGS]
$ugs1 attach-agent $udp1
$ns at 0.5 "$ugs0 start"
$ns at 1.0 "$ugs1 start"
$ns at 9.0 "$ugs1 stop"
$ns at 9.5 "$ugs0 stop"
proc finish {} {
global ns tracefd namtrace
$ns flush-trace
close $tracefd
close $namtrace
exit 0
}
#事件安排
$ns at $val(stop) "finish"
$ns at $val(stop) "puts \"NS EXISTING...\"; $ns halt"
puts "Start Simulation..."
run the simulation
$ns run
**执行ns wired_wireless2.tcl ，报错如下：
Configuration of hierarchical addressing done
num_nodes is set 4
INITIALIZE THE LIST xListHead
invalid command name "Application/Traffic/UGS"
while executing
"Application/Traffic/UGS create o137 "
invoked from within
"catch "$className create $o $args" msg"
invoked from within
"if [catch "$className create $o $args" msg] {
if [string match "_FAILED_SHADOW_OBJECT_" $msg] {
delete $o
return ""
}
global errorInfo
error "class $..."
(procedure "new" line 3)
invoked from within
"new Application/Traffic/UGS"
invoked from within
"set ugs0 [new Application/Traffic/UGS]"
(file "wired_wireless2.tcl" line 115)
执行nam文件时，没有节点。请问怎么修改呢？
