FHCF NS implementation
 

Pierre Ansel, Qiang Ni, Thierry Turletti




Copyright: You can download our ns codes freely for academic use, but please cite our contribution when you use it:

This note will help you to install our ns simulation codes of IEEE 802.11e HCF and FHCF algorithm. 

INSTALLATION:

1. Download the file fhcf.tgz. After decompressing, go into the directory /ns/ns2/. 

2. Type  

$ make install
3. Modify the shell variables LD_LIBRARY_PATH, TCL_LIBRARY and the PATH following the directions at the end of make install. 

SIMULATIONS:

FHCF can be tested with real VBR traces obtained with the VIC videoconferencing tool and the H.261 coding in the QCIF format. They correspond to a typical "head and shoulder" video sequence. 

six traces are available: 

  • vic.QCIF.30fps.1
  • vic.QCIF.30fps.2
  • vic.QCIF.30fps.3
  • vic.QCIF.30fps.4
  • vic.QCIF.30fps.5
  • vic.QCIF.30fps.6
If you want to have a description of the characteristics of the traces, you can type  
 analyze-trace trace_name
In the directory /ns/ns2/tcl/wlan, 3 scripts are available : 
  • uplink_sched-scenario.tcl:

    • It allows to test the QAP scheduler. The considered flows are audio (Burst on-off CBR), VBR H.261 video and CBR MPEG4 video. Each station sends only one traffic. 
     
  • uplink_node-scenario.tcl:

    • It allows to test also the node scheduler performance. The considered flows are the same as in uplink_sched-scenario.tcl but in this scenario, each station generates audio, VBR H.261 and CBR MPEG4 flows. 
     
  • poisson-scenario.tcl:

    • This scenario allows to show FHCF performance with flows following a poisson arrival. 
If you want to change some EDCF, TSPEC or duration parameters, or change modify the scenario, edit the scenario file. 
 

To run: 

  • EDCF: Set the HCCA duration to a very small value. FHCF and Standard HCF use the same EDCF.

    •  
  • Standard HCF: change "set std 0" to "set std 1".

    •  
  • FHCF: Use "set std 0"

    •  
To run the scenario sc-scenario.tcl, type  
 $ ns main.tcl sc
RESULTS:

To obtain statistics from the trace file sc.tr, use  

 $ wlan-stats sc
You will have the latency, throughput ... for each flow. 
 

To plot figures of latency, latency distribution, and bandwidth for the different flows, use  

 $ wlan-graphs


Qiang Ni

     Last modified: Monday, March 08, 17:35 MEST 2004