Analysis of Quality of Service in Wimax networks

Num ber of nodes
%
 
Figure 15 Packet Loss with number of nodes for UGS 
Figure 15 shows the variation of packet loss as the number of nodes with VOIP 
traffic increases for UGS service flow. There in no packet loss for the traffic with 6 
nodes. For higher number of nodes, small percent packet loss is observed. This is 
justified by the fact that the BS allocates periodic bandwidth to the MS. 
Figure 16 shows the variation of average jitter for the VOIP traffic over UGS 
service flow. 
Service Flow Type: Unsolicited Grant Service(UGS) 
Traffic Type: VOIP 
VOIP Codec: G.711 ((64kbps): 80 bytes frame, 160 bytes payload, 50 pkts per sec.) 

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Average Jitter
0.00E+00
1.00E-10
2.00E-10
3.00E-10
4.00E-10
5.00E-10
6.00E-10
7.00E-10
0
2
4
6
8
10
12
Num ber of nodes
se
co
n
d
s
 
Figure 16 Average Jitter with number of nodes for UGS 
The average jitter does not show significant variation with number of nodes. The 
values are very low and practically insignificant. 
Average Delay
0.000167166
0.000167166
0.000167166
0.000167166
0.000167166
0.000167166
0.000167166
0.000167166
0
2
4
6
8
10
12
Num ber of nodes
sec
o
n
d
s
 
Figure 17 Average Delay with number of nodes for UGS 
Service Flow Type: Unsolicited Grant Service(UGS) 
Traffic Type: VOIP 
VOIP Codec: G.711 ((64kbps): 80 bytes frame, 160 bytes payload, 50 pkts per sec.) 
Service Flow Type: Unsolicited Grant Service(UGS) 
Traffic Type: VOIP 
VOIP Codec: G.711 ((64kbps): 80 bytes frame, 160 bytes payload, 50 pkts per sec.) 

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46
Figure 17 shows Average Delay for UGS service flow as number of nodes 
increases. The values are very small, so even though the graph seems to show some 
anomalies, for all practical purposes, the average delay does not have change much when 
the number of nodes increases.