Background of Wireless Communication Student Presentations and Projects Wireless Communication Technology Wireless Networking and Mobile IP Wireless Local Area Networks Wireless Communication : LAB 4 NS2 – Extracting Trace Data

Outline  NS Trace Extraction overview  Visual representation of data  Introducing AWK

NS Trace Extraction?  Trace File generated by NS contains:  Trace packets on all links (ns trace-all)  Trace events for the complete simulation  Trace packets of all types  Event indicators of 4 types i.e. r, +, -, d  Simulation often requires comparison between two values e.g.  Pakets Dropped vs. Time  Throughput vs. Time  Number of Packets Received in specific time period  UDP vs TCP performance

Trace file Example #Open the Trace file  set tf [open out.tr w]  $ns trace-all $tf

Tracing – The Hard way !  cat out.tr | grep " 2 3 cbr " | grep ^r | column 1 10 | awk '{dif = $2 - old2; if(dif==0) dif = 1; if(dif > 0) {printf("%d\t%f\n", $2, ($1 - old1) / dif); old1 = $1; old2 = $2}}' > jitter.txt

Data Visualization Xgraph  Convert trace output into xgraph format

Example Lab Assignment

Example Lab Time-Line

Example Lab Requirements

What to Submit  TCL File/Files  Script to parse the Trace Files (bash, awk)  Generated Graph Diagrams (JPG format)  README text file containing instructions/procedures to test your code  All the files should be zipped into a single compressed file, renamed as your_reg_no_lab4.zip  zip file to

QUESTIONS  ???