Analysis of Quality of Service in Wimax networks

Equation 4 Packet Loss 
Packet loss calculation is relatively simple. The sum of the packet size of all 
packets that are sent is calculated. Next, the sum of all packets that are received is 
calculated. The difference in the two values gives the data that was lost. The ratio of 
total data lost and the total data that was sent gives the packet loss. 
A PERL script was written to analyze the ns-2 trace files and calculate the 
four parameters. It is included in the appendix for reference. 

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CHAPTER 4 
SIMULATION RESULTS 
To analyze the quality of service in WiMAX network, various real life use cases 
are considered. WiMAX provides basic IP connectivity. Mobile devices capable of 
using WiMAX network will need to support voice calling over the internet protocol.
Thus, VOIP is the first application considered. With the availability of a larger data pipe, 
another common application these days is viewing videos over the internet. So video 
streaming is analyzed as well. In this chapter, the simulation results are presented. The 
QoS parameters obtained for VOIP traffic are presented first. The multimedia traffic 
results follow.
 
4.1 VOIP traffic 
A number of nodes are placed in the coverage area of the base station and VOIP 
traffic is attached to each node. The VOIP traffic is a CBR (Constant Bit Rate) flow with 
size of packet and packet rate governed by the codec which is used. Table 3 shows the 
details of the various VOIP codecs that were used and parameters applicable. 

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Table 3 Details for VOIP Codecs 
Name Throughput 
in kbps 
Payload