1. Network Simulator 2

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

3. OTcl Tcl introduction  Cross-platform, extensible, scripting language  Interpreter language  Easy to use OTcl = Object Tcl

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

5. Homework 1/4 Studying to use ns2 to simulate TCP Network Network model:  Generating network model according to following graphic ： 0 2 15 6 7 8 34

6. Homework 2/4 Network model :  For all link: Duplex Bandwidth set to 10Mbps 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

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

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

9. Conference http://www.isi.edu/nsnam/ns/ http://140.116.72.80/~smallko/ns2/ns2.htm http://nile.wpi.edu/NS/ http://www.isi.edu/nsnam/ns/tutorial/ http://www.isi.edu/nsnam/ns/ns- documentation.html http://www.isi.edu/nsnam/ns/ns- documentation.html