在NS2上为给定的任意数量的节点创建随机有线拓扑 [英] Creating random wired topology for given arbitrary number of nodes on NS2
问题描述
我想使用NS2创建和模拟有线拓扑.尝试编写tcl并使用rand()定位节点和链接. 我的解决方案是:
I want to create and simulate a wired topology using NS2. Trying to write a tcl and positioning the nodes and links using rand() . My solution was:
### Create a simulator object
set ns [new Simulator]
set num_node 10
set num_flow 5
set x_dim 150
set y_dim 150
### Define different colors for data flows (for NAM)
$ns color 1 Blue
$ns color 2 Red
### Open the NAM trace file
set nf [open out.nam w]
$ns namtrace-all $nf
set tracefd [open out.tr w]
$ns trace-all $tracefd
### set up topography object
set topo [new Topography]; # This is needed for wireless
$topo load_flatgrid $x_dim $y_dim; # Setting a 2D space for the nodes
### Define a 'finish' procedure
proc finish {} {
global ns nf tracefd
$ns flush-trace
### Close the NAM trace file
close $nf
close $tracefd
### Execute NAM on the trace file
exec nam out.nam &
exit 0
}
#Create four nodes
for {set i 0} {$i < [expr $num_node]} {incr i} {
set n($i) [$ns node]
puts "Created node $i"
}
### Create links between the nodes
for {set i 0} {$i < [expr $num_node + 1]} {incr i} {
set s_node [expr int($num_node*rand())]; # src node
set d_node $s_node
while {$d_node==$s_node} { ; # while the random pair are same node
set d_node [expr int($num_node*rand())]; # dest node
}
$ns duplex-link $n($s_node) $n($d_node) 2Mb 10ms DropTail
$ns queue-limit $n($s_node) $n($d_node) 50
puts "Linking $s_node and $d_node"
}
### Give node position (for NAM)
set i 0
while {$i < $num_node } {
### Set random position for nodes
set x_pos [expr int($x_dim*rand())]; # random settings
set y_pos [expr int($y_dim*rand())]; # random settings
$n($i) set X_ $x_pos
$n($i) set Y_ $y_pos
$n($i) set Z_ 0.0
puts "Put $i to ($x_pos , $y_pos)"
#puts -nonewline $topofile "$i x: [$node_($i) set X_] y: [$node_($i) set Y_] \n"
incr i;
};
### Setup UDP connections
for {set i 0} {$i < [expr $num_flow]} {incr i} {
set s_node [expr int($num_node*rand())]; # src node
set d_node $s_node
while {$d_node==$s_node} {; # while the random pair are same node
set d_node [expr int($num_node*rand())]; # dest node
}
set udp($i) [new Agent/UDP]
$udp($i) set class_ $i
$ns attach-agent $n($s_node) $udp($i)
set null($i) [new Agent/Null]
$ns attach-agent $n($d_node) $null($i)
$ns connect $udp($i) $null($i)
$udp($i) set fid_ $i
puts "Flow $s_node - $d_node"
}
### Setup a CBR over UDP connections
for {set i 0} {$i < [expr $num_flow]} {incr i} {
set cbr($i) [new Application/Traffic/CBR]
$cbr($i) attach-agent $udp($i)
$cbr($i) set type_ CBR
$cbr($i) set packet_size_ 1000
$cbr($i) set rate_ 1mb
$cbr($i) set random_ false
puts "setting cbr for $i"
}
### Schedule events for the CBR and FTP agents
for {set i 0} {$i < [expr $num_flow]} {incr i} {
$ns at 0.1 "$cbr($i) start"
}
for {set i 0} {$i < [expr $num_flow]} {incr i} {
$ns at 4.5 "$cbr($i) stop"
}
for {set i 0} {$i < [expr $num_node] } { incr i} {
$ns initial_node_pos $n($i) 4
}
### Run the simulation
$ns run
但是随机化通常会创建错误的链接，从而在仿真中出现问题并得到此错误:
But the randomization is often creating erroneous links and thus problem in simulation and getting this error :
--- Classfier::no-slot{} default handler (tcl/lib/ns-lib.tcl) ---
_o28: no target for slot 4294967295
_o28 type: Classifier/Hash/Dest
content dump:
classifier _o28
0 offset
0 shift
1073741823 mask
1 slots
slot 5: _o268 (Classifier/Port)
-1 default
---------- Finished standard no-slot{} default handler ----------
但这也是随机的，并不总是发生.如果未发生，则nam文件显示节点的定义重复. 有人可以给我一些有关如何创建具有随机有效链接的随机有线拓扑的指导吗?
But this is also random and does not occur always. When it does not occur , the nam file shows that there have been duplicate definition of nodes. Can someone please just give me some guidance about how to create a random wired topology with random valid links?
推荐答案
您的文件"random-wired.tcl"在这里正常运行... PCLinuxOS 2017.04-x86_64.
Your file "random-wired.tcl" is working OK here ... PCLinuxOS 2017.04 - x86_64.
$ ns235-64-orig random-wired.tcl
Created node 0
Created node 1
Created node 2
Created node 3
Created node 4
Created node 5
Created node 6
Created node 7
Created node 8
Created node 9
Linking 9 and 0
Linking 9 and 8
Linking 5 and 8
Linking 1 and 6
Linking 9 and 6
Linking 8 and 0
Linking 1 and 4
Linking 3 and 7
Linking 8 and 7
Linking 1 and 2
Linking 9 and 0
Put 0 to (139 , 71)
Put 1 to (107 , 146)
Put 2 to (14 , 9)
Put 3 to (16 , 23)
Put 4 to (89 , 30)
Put 5 to (26 , 65)
Put 6 to (46 , 76)
Put 7 to (87 , 31)
Put 8 to (12 , 105)
Put 9 to (89 , 56)
Flow 6 - 4
Flow 0 - 1
Flow 2 - 8
Flow 5 - 2
Flow 2 - 3
setting cbr for 0
setting cbr for 1
setting cbr for 2
setting cbr for 3
setting cbr for 4
创建文件out.nam 3.3MB，out.tr 1.4MB.和nam:某些节点显示活动.
The files out.nam 3.3MB, out.tr 1.4MB are created. And nam : Some nodes show activity.
--- Classfier :: no-slot {}默认处理程序(tcl/lib/ns-lib.tcl)---
--- Classfier::no-slot{} default handler (tcl/lib/ns-lib.tcl) ---
...是某些模拟/某些Linux OS的已知错误.另一个ns2友好的OS是CentOS 7-64bit:您的文件运行正常.不好的消息:Ubuntu 16.04-64和Ubuntu 17.04-64失败.实际上，Ubuntu并不是ns2的首选. ns2不太友好，因为它的不同"补丁例如libc6.
... is an known error with some simulations / some Linux OS´s. Another ns2 friendly OS is CentOS 7 - 64bit : Your file runs OK. The not so good news : Fails with Ubuntu 16.04 - 64 and Ubuntu 17.04 - 64. Actually Ubuntu isn't the first choice for ns2. Not very ns2 friendly with it's "different" patching of e.g. libc6.
示例，rand(): aodv18.tcl ，aodv_802_15_4.tcl，AODV-Jenova.tcl，aodv-Soumia.tcl， AODV-testcode-rand.tcl → https://drive.google.com/file/d/0B7S255p3kFXNMXRfTTlEcm5KUW8/view?usp =共享
Examples, rand() : aodv18.tcl, aodv_802_15_4.tcl, AODV-Jenova.tcl, aodv-Soumia.tcl, AODV-testcode-rand.tcl → https://drive.google.com/file/d/0B7S255p3kFXNMXRfTTlEcm5KUW8/view?usp=sharing
编辑，2017年5月26日:
EDIT, May26 2017:
--- Classfier :: no-slot {}默认处理程序
--- Classfier::no-slot{} default handler
I think a solution was found http://www.linuxquestions.org/questions/linux-software-2/ns2-2-35-antnet-4175532576/#14 (post #14 @newthink) → Add $ns multicast :
set ns [ new Simulator ]
$ns multicast
与有问题的Antnet仿真完美配合.
Works perfect with the problematic Antnet simulations.
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