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Hands-On Networking: Experiment 15.2 (An Emulab Approach) Home > Student > Experiments > Emulab > 15.2

Chapter 15: Experiment 15.2 - Assign Fixed Length IP Subnet Addresses

There are two changes that need to be made to Experiment 15.1 to represent a solution to 15.2. The topology needs to be changed significantly, and the netmasks need to be a bit different. Fortunately, there is a command which does the trick: tb-set-mask. The following does not represent the topology given in Experiment 15.2. Later!

set ns [new Simulator]
source tb_compat.tcl

set node12 [$ns node]
set node13 [$ns node]
set node14 [$ns node]
set node15 [$ns node]
set node16 [$ns node]

set lan2 [$ns make-lan "$node12 $node13 $node16 " 100Mb 0ms]
set lan3 [$ns make-lan "$node14 $node15 $node16 " 100Mb 0ms]

tb-set-ip-lan $node12 $lan2
tb-set-ip-lan $node13 $lan2
tb-set-ip-lan $node16 $lan2
tb-set-netmask $lan2 ""

tb-set-ip-lan $node14 $lan3
tb-set-ip-lan $node15 $lan3
tb-set-ip-lan $node16 $lan3
tb-set-netmask $lan3 ""

$ns rtproto Static
$ns run

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