Network Simulator 2 Introduction Open source network simulator

Network Simulator 2

Introduction Open source network simulator n NS uses two languages: C++ and OTcl n ¨ C++ is fast n Kernel to run but slower to change ¨ OTcl runs much slower but can be changed very quickly n n Simulation Model Support Linux and Windows

OTcl n Tcl introduction ¨ Cross-platform, extensible, scripting language ¨ Interpreter language ¨ Easy to use n OTcl = Object Tcl

Simulation Step 1. Creating network model n 2. Creating traffic model n n 3. 4. 5. Node, link, etc… Traffic generator agent TCP/UDP agent Simulation starting Packet trace and gather statistics Result analysis

Homework 1/4 n n Studying to use ns 2 to simulate TCP Network model: ¨ Generating graphic： network model according to following 6 0 1 7 5 2 8 3 4

Homework 2/4 n Network model : ¨ For all link: n Duplex n Bandwidth set to 10 Mbps n Traffic model: ¨ Setup a FTP over TCP connection from node 8 to node 0 ¨ Setup a CBR over UDP connection from node 3 to node 6 ¨ Set the starting time by yourself

Homework 3/4 n Simulation: ¨ ¨ n Changing the CBR data rate to 1, 4, 8 Mbps Packet size 500 Run simulation Simulation time 100 s Packet trace and gather statistics ¨ ¨ End to end delay Throughput Deliver rate Graphic

Homework 4/4 n Result analysis ¨ Explain n n Data rate Time End to end delay Throughput Deliver rate ¨ Explain n the relationship between the reason why packet loss Deadline : 11/25

Conference http: //www. isi. edu/nsnam/ns/ n http: //140. 116. 72. 80/~smallko/ns 2. htm n http: //nile. wpi. edu/NS/ n http: //www. isi. edu/nsnam/ns/tutorial/ n http: //www. isi. edu/nsnam/ns/nsdocumentation. html n