The following statistical techniques are used to study the long-range dependence
of network traffic:
-
Aggregated variance
-
Whittle method (this is
an excerpt from Prof
Richard Smith's talk on October 29th 2002)
-
Wavelet
analysis
The data is available from the following web pages:
-
Real data: data taken
at the UNC campus link.
-
Synthetic data: data
generated by web traffic generators simulating users browsing the web.
For easy access, the data sets are also linked in the left hand column
of the tables of results given here.
We apply the aforementioned techniques to both real network data taken
at the UNC campus link and synthetic data generated in our lab. The table
below contains the estimation of the Hurst parameter from those techniques.
Each entry in the table also contains a link to the detailed plots for
the estimates.
The plots of the Whittle method are by courtesy of
Prof.
Richard Smith. The Hurst parameter from the Whittle method was obtained
by a course estimation of the confidence intervals on d (where H = d +
1/2) from visual inspection of the plots. Please refer to the plots of
the d parameter by following the links in the Whittle method column.
The Hurst parameters from the wavelet analysis shown below are obtained
from data sampled at 1-ms intervals. Results from higher aggregation levels
are also available for synthetic
data and real data.
The numbers in parentheses represent the confidence interval for the wavelet
analysis.
While most of the data files have only a single column, some have two
columns of data, which give byte and packet counts. In all analyses here
we consider only the packet counts (second column).
The following results are compared using scatterplots in the web page
Comparative Plots
of Hurst Parameter Estimation Methods.
Automatic
| Data |
Aggregated variance |
Whittle method (Richard) |
Whittle method (Michele) |
Wavelet
method |
SiZer
plots |
| 18
clients, 10 servers, 20 Mbps |
H = 0.82 |
H = 0.899 (0.848 - 0.950) |
H =0.8329 (0.8169 - 0.8490) |
H = 0.86 (0.82 - 0.89) |
SiZer plot |
| 18
clients, 10 servers, 50 Mbps |
H = 0.83 |
H = 0.880 (0.831 - 0.928) |
H =0.8481 (0.8166 - 0.8795) |
H = 0.87 (0.83 - 0.90) |
SiZer plot |
| 18
clients, 10 servers, 80 Mbps |
H = 0.84 |
H = 0.845 (0.801 - 0.890) |
H =0.8294 (0.8001 - 0.8587) |
H = 0.84 (0.81 - 0.87) |
SiZer plot |
| 18
clients, 10 servers, 110 Mbps |
H = 0.85 |
H = 0.900 (0.854 - 0.946) |
H =0.8570 (0.8193 - 0.8947) |
H = 0.90 (0.85 - 0.96) |
SiZer plot |
| 18
clients, 10 servers, 140 Mbps |
H = 0.83 |
H = 0.852 (0.806 - 0.898) |
H =0.8342 (0.8163 - 0.8522) |
H = 0.82 (0.80 - 0.85) |
SiZer plot |
| Real
data: Mon 21:30 April 08 2002 |
H = 0.86 |
H = 0.969 (0.922 -
1.015) |
H = 0.99 (0.96 - 1.03) |
H = 0.99 (0.95 - 1.03) |
SiZer plot |
| Real
data: Tue 03:00 April 09 2002 |
H = 0.95 |
H = 1.281 (1.229 -
1.332) |
H = 1.26 (1.22 - 1.29) |
H = 1.14 (1.10 - 1.18) |
SiZer plot |
| Real
data: Tue 05:00 April 09 2002 |
H = 0.86 |
H = 1.070 (1.020 -
1.119) |
H = 1.05 (1.02 - 1.08) |
H = 1.02 (0.96 - 1.08) |
SiZer plot |
| Real
data: Tue 08:00 April 09 2002 |
H = 0.98 |
H = 1.258 (1.214 -
1.301) |
H = 1.18 (1.15 - 1.21) |
H = 0.95 (0.91 - 0.99) |
SiZer plot |
| Real
data: Tue 13:00 April 09 2002 |
H = 0.90 |
H = 1.009 (0.970 -
1.047) |
H = 0.97 (0.95 - 1.00) |
H = 0.91 (0.88 - 0.93) |
SiZer plot |
| Real
data: Tue 19:30 April 09 2002 |
H = 0.86 |
H = 0.983 (0.938 -
1.028) |
H = 0.96 (0.93 - 0.99) |
H = 0.91 (0.89 - 0.94) |
SiZer plot |
| Real
data: Wed 13:00 April 10 2002 |
H = 0.87 |
H = 0.978 (0.936 -
1.020) |
H = 0.98 (0.95 - 1.01) |
H = 0.95 (0.91 - 0.99) |
SiZer plot |
| Real
data: Wed 21:30 April 10 2002 |
H = 0.85 |
H = 0.981 (0.935 -
1.026) |
H = 0.97 (0.94 - 1.01) |
H = 0.98 (0.94 - 1.02) |
SiZer plot |
| Real
data: Thu 03:00 April 11 2002 |
H = 0.92 |
H = 1.093 (1.052 -
1.134) |
H =1.03 (1.01 - 1.06) |
H = 0.96 (0.92 - 1.00) |
SiZer plot |
| Real
data: Thu 10:00 April 11 2002 |
H = 0.94 |
H = 1.085 (1.044 -
1.125) |
H = 1.02 (1.00 - 1.05) |
H = 0.96 (0.92 - 1.00) |
SiZer plot |
| Real
data: Thu 13:00 April 11 2002 |
H = 0.87 |
H = 0.828 (0.781 -
0.875) |
H = 1.06 (1.02 - 1.11) |
H = 0.79 (0.50 - 1.09) |
SiZer plot |
| Real
data: Thu 15:00 April 11 2002 |
H = 0.86 |
H = 0.948 (0.905 -
0.992) |
H = 0.95 (0.92 - 0.99) |
H = 0.91 (0.88 - 0.94) |
SiZer plot |
| Real
data: Thu 19:30 April 11 2002 |
H = 0.86 |
H = 0.970 (0.923 -
1.017) |
H = 0.98 (0.95 - 1.01) |
H = 0.94 (0.92 - 0.97) |
SiZer plot |
| Real
data: Fri 03:00 April 12 2002 |
H = 0.96 |
H = 1.183 (1.142 -
1.224) |
H = 1.12 (1.09 - 1.14) |
H = 1.00 (0.94 - 1.06) |
SiZer plot |
| Real
data: Fri 21:30 April 12 2002 |
H = 0.85 |
H = 0.987 (0.942 -
1.032) |
H = 0.94 (0.91 - 0.97) |
H = 0.95 (0.91 - 0.99) |
SiZer plot |
| Real
data: Sat 10:00 April 13 2002 |
H = 0.90 |
H = 1.000 (0.960 -
1.040) |
H = 1.01 (0.98 - 1.03) |
H = 0.94 (0.77 - 1.10) |
SiZer plot |
| Real
data: Sat 13:00 April 13 2002 |
H = 0.94 |
H = 1.222 (1.183 -
1.261) |
H = 1.11 (1.08 - 1.13) |
H = 1.48 (1.32 - 1.64) |
SiZer plot |
| Real
data: Sat 15:00 April 13 2002 |
H = 0.89 |
H = 1.029 (0.986 -
1.071) |
H = 1.00 (0.97 - 1.03) |
H = 1.00 (0.94 - 1.06) |
SiZer plot |
| Real
data: Sat 19:30 April 13 2002 |
H = 0.83 |
H = 0.906 (0.862 -
0.951) |
H = 0.92 (0.89 - 0.95) |
H = 0.89 (0.87 - 0.92) |
SiZer plot |
| Real
data: Sat 21:30 April 13 2002 |
H = 0.86 |
H = 1.011 (0.964 -
1.059) |
H = 0.99 (0.95 - 1.02) |
H = 0.94 (0.91 - 0.96) |
SiZer plot |
"Tuned"
| Data |
Aggregated variance |
Whittle method |
Whittle method (Michele) |
Wavelet
method |
SiZer
plots |
| 18
clients, 10 servers, 20 Mbps |
H = 0.82 |
H = (0.8 - 0.88) |
H =0.8542 (0.8163 - 0.8922) |
H = 0.84 (0.81 - 0.86) |
SiZer plot |
| 18
clients, 10 servers, 50 Mbps |
H = 0.82 |
H = (0.8 - 0.88) |
H =0.8728 (0.8341 - 0.9114) |
H = 0.90 (0.85 - 0.96) |
SiZer plot |
| 18
clients, 10 servers, 80 Mbps |
H = 0.83 |
H = (0.8 - 0.88) |
H =0.8488 (0.8039 - 0.8937) |
H = 0.85 (0.82 - 0.88) |
SiZer plot |
| 18
clients, 10 servers, 110 Mbps |
H = 0.84 |
H = (0.8 - 0.86) |
H =0.9014 (0.8554 - 0.9474) |
H = 0.88 (0.82 - 0.94) |
SiZer plot |
| 18
clients, 10 servers, 140 Mbps |
H = 0.82 |
H = (0.8 - 0.85) |
H =0.8596 (0.8138 - 0.9053) |
H = 0.82 (0.80 - 0.85) |
SiZer plot |
| Real
data: Mon 21:30 April 08 2002 |
H = 0.91 |
H = (0.88 - 0.93) |
H = 0.99 (0.96 - 1.03) |
H = 1.00 (0.96 - 1.04) |
SiZer plot |
| Real
data: Tue 03:00 April 09 2002 |
H = 0.98 |
H = (0.87 - 0.92) |
H = 1.26 (1.22 - 1.29) |
H = 1.06 (1.01 - 1.10) |
SiZer plot |
| Real
data: Tue 05:00 April 09 2002 |
H = 0.93 |
H = (0.86 - 0.92) |
H = 1.06 (1.03 - 1.09) |
H = 1.07 (1.00 - 1.14) |
SiZer plot |
| Real
data: Tue 08:00 April 09 2002 |
H = 0.99 |
H = (1.0 - 1.06) |
H = 1.25 (1.21 - 1.29) |
H = 0.93 (0.89 - 0.98) |
SiZer plot |
| Real
data: Tue 13:00 April 09 2002 |
H = 0.96 |
H = (0.88 - 0.92) |
H = 1.03 (0.99 - 1.08) |
H = 0.91 (0.88 - 0.93) |
SiZer plot |
| Real
data: Tue 19:30 April 09 2002 |
H = 0.91 |
H = (0.9 - 0.94) |
H = 0.98 (0.94 - 1.03) |
H = 0.95 (0.91 - 0.99) |
SiZer plot |
| Real
data: Wed 13:00 April 10 2002 |
H = 0.93 |
H = (0.87 - 0.92) |
H = 0.98 (0.95 - 1.02) |
H = 0.97 (0.93 - 1.01) |
SiZer plot |
| Real
data: Wed 21:30 April 10 2002 |
H = 0.91 |
H = (0.88 - 0.93) |
H = 0.98 (0.93 - 1.02) |
H = 0.98 (0.94 - 1.02) |
SiZer plot |
| Real
data: Thu 03:00 April 11 2002 |
H = 0.98 |
H = |
H =1.03 (1.01 - 1.06) |
H = 0.97 (0.93 - 1.02) |
SiZer plot |
| Real
data: Thu 10:00 April 11 2002 |
H = 0.98 |
H = |
H = 1.04 (1.01 - 1.07) |
H = 1.00 (0.93 - 1.07) |
SiZer plot |
| Real
data: Thu 13:00 April 11 2002 |
H = 0.93 |
H = |
H = 1.10 (1.08 - 1.13) |
H = 0.82 (0.30 - 1.34) |
SiZer plot |
| Real
data: Thu 15:00 April 11 2002 |
H = 0.90 |
H = |
H = 0.95 (0.90 - 0.99) |
H = 0.91 (0.88 - 0.94) |
SiZer plot |
| Real
data: Thu 19:30 April 11 2002 |
H = 0.91 |
H = |
H = 0.97 (0.92 - 1.02) |
H = 0.96 (0.93 - 0.98) |
SiZer plot |
| Real
data: Fri 03:00 April 12 2002 |
H = 0.99 |
H = |
H = 1.18 (1.14 - 1.22) |
H = 1.04 (0.98 - 1.11) |
SiZer plot |
| Real
data: Fri 21:30 April 12 2002 |
H = 0.91 |
H = |
H = 0.94 (0.91 - 0.97) |
H = 0.94 (0.90 - 0.98) |
SiZer plot |
| Real
data: Sat 10:00 April 13 2002 |
H = 0.96 |
H = |
H = 1.02 (0.98 - 1.06) |
H = 0.91 (0.86 - 0.95) |
SiZer plot |
| Real
data: Sat 13:00 April 13 2002 |
H = 0.98 |
H = |
H = ??? (??? - ???) |
H = 1.49 (1.11 - 1.87) |
SiZer plot |
| Real
data: Sat 15:00 April 13 2002 |
H = 0.95 |
H = |
H = 1.03 (0.99 - 1.07) |
H = 0.97 (0.93 - 1.01) |
SiZer plot |
| Real
data: Sat 19:30 April 13 2002 |
H = 0.87 |
H = |
H = 0.91 (0.86 - 0.96) |
H = 0.90 (0.88 - 0.93) |
SiZer plot |
| Real
data: Sat 21:30 April 13 2002 |
H = 0.91 |
H = |
H = 0.99 (0.95 - 1.02) |
H = 0.98 (0.91 - 1.06) |
SiZer plot |
Detrended data
| Data |
Aggregated variance |
Whittle method (Richard) |
Whittle method (Michele) |
Wavelet
method |
SiZer
plots |
| 18 clients, 10 servers,
20 Mbps |
H = 0.82 |
H = 0.899 (0.848
- 0.950) |
H =0.8332 (0.8175 - 0.8489 |
H = 0.86 (0.82
- 0.89) |
SiZer plot |
| 18 clients, 10 servers,
50 Mbps |
H = 0.83 |
H = 0.879 (0.830
- 0.928) |
H =0.8617 (0.8312 - 0.8922) |
H = 0.87 (0.83
- 0.90) |
SiZer plot |
| 18 clients, 10 servers,
80 Mbps |
H = 0.84 |
H = 0.845 (0.800
- 0.890) |
H =0.8500 (0.8316 - 0.8684) |
H = 0.84 (0.81
- 0.87) |
SiZer plot |
| 18 clients, 10 servers,
110 Mbps |
H = 0.85 |
H = 0.901
(0.854 - 0.947) |
H =0.9078 (0.8759 - 0.9397) |
H = 0.90 (0.85
- 0.96) |
SiZer plot |
| 18 clients, 10 servers,
140 Mbps |
H = 0.83 |
H = 0.852
(0.806 - 0.897) |
H =0.8331 (0.8149 - 0.8513) |
H = 0.82 (0.80
- 0.85) |
SiZer plot |
| Real data: Mon 21:30 April
08 2002 |
H = 0.86 |
H = 0.969
(0.922 - 1.016) |
H = 1.00 (0.96 - 1.03) |
H = 0.99 (0.95
- 1.03) |
SiZer plot |
| Real data: Tue 03:00 April
09 2002 |
H = 0.95 |
H = 1.280
(1.228 - 1.332) |
H = 1.26 (1.22 - 1.29) |
H = 1.14 (1.10
- 1.18) |
SiZer plot |
| Real data: Tue 05:00 April
09 2002 |
H = 0.86 |
H = 1.069
(1.019 - 1.119) |
H = 1.05 (1.02 - 1.08) |
H = 1.02 (0.96
- 1.08) |
SiZer plot |
| Real data: Tue 08:00 April
09 2002 |
H = 0.91 |
H = 1.096
(1.051 - 1.141) |
H = 1.22 (1.19 - 1.24) |
H = 0.95 (0.91
- 0.99) |
SiZer plot |
| Real data: Tue 13:00 April
09 2002 |
H = 0.86 |
H = 0.960
(0.916 - 1.003) |
H = 0.99 (0.97 - 1.02) |
H = 0.91 (0.88
- 0.93) |
SiZer plot |
| Real data: Tue 19:30 April
09 2002 |
H = 0.86 |
H = 0.983
(0.939 - 1.028) |
H = 0.96 (0.93 - 0.99) |
H = 0.91 (0.89
- 0.94) |
SiZer plot |
| Real data: Wed 13:00 April
10 2002 |
H = 0.84 |
H = 0.950
(0.906 - 0.995) |
H = 0.99 (0.96 - 1.02) |
H = 0.95 (0.91
- 0.99) |
SiZer plot |
| Real data: Wed 21:30 April
10 2002 |
H = 0.85 |
H = 0.977
(0.931 - 1.023) |
H = 0.97 (0.94 - 1.01) |
H = 0.98 (0.94
- 1.02) |
SiZer plot |
| Real data: Thu 03:00 April
11 2002 |
H = 0.84 |
H = 0.982
(0.936 - 1.028) |
H =1.07 (1.04 -1.10) |
H = 0.96 (0.92
- 1.00) |
SiZer plot |
| Real data: Thu 10:00 April
11 2002 |
H = 0.87 |
H = 1.006
(0.962 - 1.051) |
H = 1.05 (1.02 - 1.08) |
H = 0.96 (0.92
- 1.00) |
SiZer plot |
| Real data: Thu 13:00 April
11 2002 |
H = 0.86 |
H = 0.802
(0.752 - 0.852) |
H = 1.07 (1.02 - 1.11) |
H = 0.79 (0.50
- 1.09) |
SiZer plot |
| Real data: Thu 15:00 April
11 2002 |
H = 0.85 |
H = 0.939
(0.894 - 0.983) |
H = 0.96 (0.93 - 0.99) |
H = 0.91 (0.88
- 0.94) |
SiZer plot |
| Real data: Thu 19:30 April
11 2002 |
H = 0.86 |
H = 0.966
(0.919 - 1.013) |
H = 0.98 (0.95 - 1.01) |
H = 0.94 (0.92
- 0.97) |
SiZer plot |
| Real data: Fri 03:00 April
12 2002 |
H = 0.84 |
H = 1.031
(0.983 - 1.079) |
H = 1.16 (1.13 - 1.18) |
H = 1.00 (0.94
- 1.06) |
SiZer plot |
| Real data: Fri 21:30 April
12 2002 |
H = 0.85 |
H = 0.987
(0.942 - 1.033) |
H = 0.94 (0.91 - 0.97) |
H = 0.95 (0.91
- 0.99) |
SiZer plot |
| Real data: Sat 10:00 April
13 2002 |
H = 0.84 |
H = 0.919
(0.875 - 0.963) |
H = 1.03 (1.00 - 1.06) |
H = 0.94 (0.77
- 1.10) |
SiZer plot |
| Real data: Sat 13:00 April
13 2002 |
H = 0.94 |
H = 1.222
(1.183 - 1.261) |
H = 1.11 (1.08 - 1.13) |
H = 1.48 (1.32
- 1.64) |
SiZer plot |
| Real data: Sat 15:00 April
13 2002 |
H = 0.89 |
H = 1.029
(0.986 - 1.072) |
H = 1.01 (0.98 - 1.04) |
H = 1.00 (0.94
- 1.06) |
SiZer plot |
| Real data: Sat 19:30 April
13 2002 |
H = 0.83 |
H = 0.906
(0.861 - 0.951) |
H = 0.92 (0.89 - 0.96) |
H = 0.89 (0.87
- 0.92) |
SiZer plot |
| Real data: Sat 21:30 April
13 2002 |
H = 0.86 |
H = 1.011
(0.964 - 1.059) |
H = 0.99 (0.95 - 1.02) |
H = 0.94 (0.91
- 0.96) |
SiZer plot |
Simulated data (automatic)
Simulated data ("tuned")
Dependent
SiZer Web page
Wavelet
coefficients + SiZer
Long Le, Félix Hernández-Campos ({le,fhernand}@cs.unc.edu)
Created: Sat Jul 7 17:29:02 EDT 2001Last
Modified: Sat Aug 7 9:37:00 EDT 2004 by F. Hernández-Campos |
|