Wireshark-users: Re: [Wireshark-users] Jitter wrong in wireshark?
Date: Fri, 23 Feb 2007 11:29:05 -0600
Title: Jitter wrong in wireshark?
Hi Anders,
good question. I´m not sure but I guess is codec is PCMA G711 8KHz (will take a look during call setup in a couple of hours).
 
However "Payload type" is 97 (0x61), and wireshark shows it as "Payload type=Unknown"
 
According to the formula, jitter calculation depends on timestamps and arrival time differences. I don´t know how codec could affect.
 
BR
Juan
 


From: [email protected] [mailto:[email protected]] On Behalf Of ext Anders Broman (AL/EAB)
Sent: Viernes, 23 de Febrero de 2007 01:05 p.m.
To: Community support list for Wireshark
Subject: SV: [Wireshark-users] Jitter wrong in wireshark?

Hi,
Which codec is used?
Best regards
Anders


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Skickat: fr 2007-02-23 16:53
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Ämne: [Wireshark-users] Jitter wrong in wireshark?

Hi All,

Below is a rtp analysis from a wireshark 0.99.5 capture in a live network.

Doing by hand jitter calculation it doesn´t match. And of course, if below data is real it means we are having jitter of more than 1 minute !!

Exampe: first jitter should be 138.90/16 = 8.68125 [ms] and is showing 8803,82 [ms] !!!

Do someone know what could be wrong or what I´m missing?

BR
Juan


Forward                                                                
Packet  Sequence        Delta (ms)     
Jitter (ms)     IP BW (kbps)    Marker  Status  Date    Length 
1       0       0.00   
0.00    1.45            [ Ok ]  02/19/2007 18:44:25.915 231    
2       1       138.90 
8803.82 2.90            [ Ok ]  02/19/2007 18:44:26.053 231    
3       2       119.59 
17058.61        4.34            [ Ok ]  02/19/2007 18:44:26.173 231    
4       3       139.67 
24796.21        5.79            [ Ok ]  02/19/2007 18:44:26.313 231    
5       4       180.22 
32047.69        7.24            [ Ok ]  02/19/2007 18:44:26.493 231    
6       5       241.67 
38842.10        8.69            [ Ok ]  02/19/2007 18:44:26.735 231    
7       6       96.71  
45220.93        10.14           [ Ok ]  02/19/2007 18:44:26.831 231    
8       7       198.41 
51194.72        10.14           [ Ok ]  02/19/2007 18:44:27.030 231    
9       8       205.78 
56794.69        8.69            [ Ok ]  02/19/2007 18:44:27.235 231    
10      9       193.62 
62045.42        8.69            [ Ok ]  02/19/2007 18:44:27.429 231    
11      10      197.77 
66967.72        8.69            [ Ok ]  02/19/2007 18:44:27.627 231    
12      11      208.31 
71581.72        7.24            [ Ok ]  02/19/2007 18:44:27.835 231    
13      12      190.92 
75908.43        8.69            [ Ok ]  02/19/2007 18:44:28.026 231    
14      13      199.23 
79964.20        8.69            [ Ok ]  02/19/2007 18:44:28.225 231    
15      14      183.31 
83767.48        8.69            [ Ok ]  02/19/2007 18:44:28.409 231    
16      15      200.50 
87331.98        8.69            [ Ok ]  02/19/2007 18:44:28.609 231    
17      16      216.07 
90672.73        8.69            [ Ok ]  02/19/2007 18:44:28.825 231    
18      17      137.81 
93809.57        8.69            [ Ok ]  02/19/2007 18:44:28.963 231    
19      18      139.08 
96750.28        8.69            [ Ok ]  02/19/2007 18:44:29.102 231    
20      19      119.60 
99508.41        10.14           [ Ok ]  02/19/2007 18:44:29.222 231    
21      20      119.59 
102094.16       10.14           [ Ok ]  02/19/2007 18:44:29.341 231    
22      21      119.18 
104518.33       10.14           [ Ok ]  02/19/2007 18:44:29.460 231    
23      22      126.80 
106790.51       11.58           [ Ok ]  02/19/2007 18:44:29.587 231    
24      23      112.05 
108921.60       11.58           [ Ok ]  02/19/2007 18:44:29.699 231    
25      24      145.14 
110917.43       11.58           [ Ok ]  02/19/2007 18:44:29.844 231    
26      25      115.57 
112790.36       13.03           [ Ok ]  02/19/2007 18:44:29.960 231    
27      26      118.57 
114546.05       13.03           [ Ok ]  02/19/2007 18:44:30.079 231    
28      27      139.44 
116190.71       13.03           [ Ok ]  02/19/2007 18:44:30.218 231    
29      28      120.40 
117733.77       13.03           [ Ok ]  02/19/2007 18:44:30.338 231    
30      29      118.59 
119180.49       13.03           [ Ok ]  02/19/2007 18:44:30.457 231    
31      30      120.00 
120536.71       13.03           [ Ok ]  02/19/2007 18:44:30.577 231    
32      31      120.23 
121808.15       13.03           [ Ok ]  02/19/2007 18:44:30.697 231    
33      32      119.60 
123000.17       13.03           [ Ok ]  02/19/2007 18:44:30.817 231    
34      33      118.72 
124117.74       13.03           [ Ok ]  02/19/2007 18:44:30.936 231    
35      34      119.88 
125165.39       13.03           [ Ok ]  02/19/2007 18:44:31.055 231    
36      35      146.42 
126145.90       13.03           [ Ok ]  02/19/2007 18:44:31.202 231    
37      36      57.34  
118265.37       11.90   SET     Incorrect timestamp     02/19/2007 18:44:31.259 90     
                                                                       
Reverse                                                                
Packet  Sequence        Delta (ms)     
Jitter (ms)     IP BW (kbps)    Marker  Status  Date    Length 
44      1       0.00   
0.00    1.45            [ Ok ]  02/19/2007 18:44:36.119 231    
46      2       126.78 
99992.08        2.90            [ Ok ]  02/19/2007 18:44:36.246 231    
47      3       293.16 
193724.25       4.34            [ Ok ]  02/19/2007 18:44:36.539 231    
48      4       159.97 
281606.49       5.79            [ Ok ]  02/19/2007 18:44:36.699 231    
49      5       119.98 
363998.58       7.24            [ Ok ]  02/19/2007 18:44:36.819 231    
50      6       160.07 
441238.67       8.69            [ Ok ]  02/19/2007 18:44:36.979 231    
51      7       261.00 
513644.94       8.69            [ Ok ]  02/19/2007 18:44:37.240 231    
52      8       43.09  
481544.82       7.56    SET     Incorrect timestamp     02/19/2007 18:44:37.283 90