Difference between revisions of "Voice only analysis"

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Situation:
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== Experimental Setup ==
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Because it is impossible to measure data traffic between two VM ware's on the same machine, the following setup is used. The SIP-phones all use the g711u codec.
  
 
[[image:schematic_of_PC-config.png|Schematic overview of all PC's running which software.]]
 
[[image:schematic_of_PC-config.png|Schematic overview of all PC's running which software.]]
  
Voice-call between 201 (GSM-codec) and 301 (G711u codec)
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== Results ==
* Traffic to and from Ext. 201 is Green
 
* Traffic to and from Ext. 301 is Red
 
* Traffic between Asterisk-boxes is Blue in one direction and black in the other
 
  
Used filters in I/O-graph:
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With WireShark data has been collected and the following filters are used in the in I/O-graph:
 
  Filter-Black: ip.src == 192.168.1.101 && ip.dst == 192.168.1.106
 
  Filter-Black: ip.src == 192.168.1.101 && ip.dst == 192.168.1.106
 
  Filter-Red  : ip.src == 192.168.1.3  && ip.dst == 192.168.1.106
 
  Filter-Red  : ip.src == 192.168.1.3  && ip.dst == 192.168.1.106
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[[image:Wireshark-graph_G711_G711_traffic_Bps_oneway-traffic.png]]
 
[[image:Wireshark-graph_G711_G711_traffic_Bps_oneway-traffic.png]]
  
From the graph shown above there can be concluded that the IAX2 traffic (black and blue line) uses less bandwidth than the SIP-traffic (red and green line).
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Legenda:
We also filtered for traffic between all three SIP-telephones and no traffic was detected.
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* '''Blue''': Traffic between the Asterisk-boxes in the other direction.
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* '''Black''': Traffic between the Asterisk-boxes in one direction.
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* '''Red''': Traffic to and from SIP phone 301.
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* '''Pink''': Traffic to and from SIP phone 202.
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* '''Green''': Traffic to and from SIP phone 201.
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== Conclusions ==
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* From the graph shown above there can be concluded that the IAX2 traffic (black and blue line) uses less bandwidth than the SIP-traffic (red and green line). This is due to the IAX trunking which reduced the overhead.
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* We also filtered for traffic between all three SIP-telephones and ''no direct traffic was detected between them.''
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* The audio traffic is measured to be approximately 10500*8/1000=84kbps, which corresponds very well to the expected NEB value of 87.2 kbps.

Latest revision as of 13:08, 23 February 2007

Experimental Setup

Because it is impossible to measure data traffic between two VM ware's on the same machine, the following setup is used. The SIP-phones all use the g711u codec.

Schematic overview of all PC's running which software.

Results

With WireShark data has been collected and the following filters are used in the in I/O-graph:

Filter-Black: ip.src == 192.168.1.101 && ip.dst == 192.168.1.106
Filter-Red  : ip.src == 192.168.1.3   && ip.dst == 192.168.1.106
Filter-Green: ip.src == 192.168.1.189 && ip.dst == 192.168.1.101
Filter-Blue : ip.src == 192.168.1.106 && ip.dst == 192.168.1.101
Filter-Pink : ip.src == 192.168.1.100 && ip.dst == 192.168.1.101

Wireshark-graph G711 G711 traffic Bps oneway-traffic.png

Legenda:

  • Blue: Traffic between the Asterisk-boxes in the other direction.
  • Black: Traffic between the Asterisk-boxes in one direction.
  • Red: Traffic to and from SIP phone 301.
  • Pink: Traffic to and from SIP phone 202.
  • Green: Traffic to and from SIP phone 201.

Conclusions

  • From the graph shown above there can be concluded that the IAX2 traffic (black and blue line) uses less bandwidth than the SIP-traffic (red and green line). This is due to the IAX trunking which reduced the overhead.
  • We also filtered for traffic between all three SIP-telephones and no direct traffic was detected between them.
  • The audio traffic is measured to be approximately 10500*8/1000=84kbps, which corresponds very well to the expected NEB value of 87.2 kbps.