HighSpeed Transmission Evaluation of

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High-Speed Transmission Evaluation of Gigabit
Local Area Networks by Limiting Performance Model
Satoru Fujimoto, Kenji Tamura, Osanori Koyama
and Yutaka Katsuyama
Graduate School of Engineering, Osaka Prefecture
University
2
Background
- The internet traffic increases rapidly year by
year. - The network should be replaced with
faster products. - What is the performance?
Clients
Congestion? Replacing 10 with 100 Base?
Intranet System
Server
Hub
We want to estimate the performance simply.
What is the performance when existing hardware is
replaced with the gigabit one?
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Objectives
Many kinds of LAN performance analysis contain
probability of communication occurrence of the
clients Poisson processes

• - We have already proposed a limiting performance
  evaluation method
• for client/server LANs.
• Formulae to give a file transfer time have been
  derived.
• The calculated values were in good agreement with
  measured ones in
• 10 and 100Base LANs.

In This Presentation, ...
- The limiting performance evaluation method for
the 10 and 100Base LANs was extended to the
gigabit LAN evaluation. - High-speed transmission
evaluation of gigabit LAN is described.
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Whats presented?
We present
(1). High-Speed Transmission Evaluation of
Gigabit Local Area Networks -Transfer
Time Analysis by Extending Limiting
Performance Model Formulae to Give the Limiting
Performance -Classifying the LANs according
to the Hub Types -Measured Calculated
Results (2). Performance Improvement Evaluation
When replacing 100Base with 100/1000Base
Products -Measured Calculated
Results
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LAN Configuration to be Evaluated
IEEE 802.3 LAN
CL1
Switching or Non-Switching
CL2
Hub
Server
Congestion
CLn
CSMA/CD Back Pressure Pause Function
10Base-T 100Base-T 1000Base-T
The Packet Flow is Controlled by
Media
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Classification of Hubs
100Base-T Server 10Base-T Clients
Non-Switching (NSW) Switching (SW)
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Simultaneous Packet Transfer Model

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Packet Flow to the Server
Pause LAN
C
L

1
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n
Time
one packet transfer time
Pause LAN
Packet flow is controlled by Pause function.
unit waiting time to take a packet out the
buffer inside the hub
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Derived Formulae
Client number when 1000Mbps uploading capacity
is exhausted
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Parameters in the Formulae
Meaning
Parameter
n
Client Number
u
Unit Packet Size
Transfer Time to Send One
t
u
Packet u
Unit Waiting Time to
x
Establish the Link
Slot Time for All Ethernet
y
1
Data Rates
Unit Waiting Time to Take a Packet out the
Buffer in the Hub
y
2
Transfer Time to Send One
z
Packet u inside the Hub
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Measured and Calculated Transfer Time
Measured
10Base NSW
10Base BP
10Base Pause
100
10/100Base
100Base NSW
100Base BP
100Base Pause
100/1000Base SV2
100/1000Base SV1
Calculated
10
Transfer time (s)
1
100Mbps
100Mbps x 4400Mbps
100Mbps x 3300Mbps
0.1
2
0
4
6
8
10
Client number n
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Obtained Parameter Values
Z
LAN
(msec)
(msec)
10
1.200
0.080
x
NSW
100
0.130
0.010
10
1.273
0.051
y
BP
14608bits/10Mbps 1.2 ms (10Base) 14608bits/1
00Mbps 0.12 ms (100Base)
1
100
0.131
0.005
SW
10
1.226
0.028
y
Pause
2
100
0.123
0.002
z
1
8
n
1.264
0.010
?
?
10/100Base
x
9
n
0.142
0.010
?
z
1
n
3
0.115
0.007
100/1000Base
?
?
Server1 with a PCI-bus speed of 64bit/33MHz
y
Server1
4
n
0.026
0.033
?
2
z
1
4
n
0.115
0.006
?
?
100/1000Base
Server2 with a PCI-bus speed of 64bit/66MHz
y
Server2
5
n
0.014
0.030
?
2
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Throughput Improvement with Gigabit Technology
100Base Pause Hub
CL1
64bit/33MHz PCI-Bus Speed
CL2
Hub
Server
CLn
Replace this with
Replace this with
64bit/66MHz PCI-Bus Speed Server
100/1000Base Hub
Pause Hub
Packet flow is controlled by Pause function.
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Throughput Improvement
100
Measured
80
100Base Pause
100/1000Base SV1
100/1000Base SV2
60
Throughput (Mbps)
Calculated
Improve-
ment
40
20
0
2
4
6
8
10
Client number n
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Conclusion
(1). The limiting performance evaluation method
for the 10 and 100Base LANs was extended so as
to evaluate different types of LANs. -
Performance Evaluation Based on the Limiting
Performance Model - Simple Useful
Formulae, Including 10, 100,
10/100, 100/1000Base Hubs - Good Agreement with
Measured Values (2). A high-speed transmission
of gigabit LAN has been evaluated theoretically
and experimentally.
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Transfer Time Measurement Tool
CL1
Controller
FTP Server
CLn
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Simultaneous Packet Transfer Model for the
Evaluation CSMA/CD LAN
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