Transcript The NCTUNS 1.0 Network Simulator

NCTUns 5.0 Network Simulator
and Emulator
Prof. Shie-Yuan Wang
[email protected]
Department of Computer Science
National Chiao Tung University, Taiwan
Network and System
Laboratory
Outline


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Introduction
Architecture
NCTUns features

Simulation methodology
Product status
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Concluding remarks

Introduction
Introduction



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The NCTUns network simulator and emulator is
developed at NCTU, Taiwan. Its predecessor is
the Harvard network simulator (invented by
Prof. S.Y. Wang in 1999).
By using a novel simulation methodology, it
can do several tasks that traditional network
simulators cannot easily do.
After more than eight years’ development, it
has become a useful tool.
Many people are using it. (Use the Google to
search it for yourself.)
Now, its Impact Is Ranked #2
by Google Taiwan
The IEEE Network Magazine reports
this tool in its July 2003 issue.
Selected as a Research Demo
by ACM MobiCom’02
Again selected by
MobiCom 2003
Ranked #1 of the 12 selected
First local workshop on
12/05/2002
Second local workshop
on 12/12/2003
A Tutorial Made at IEEE Vehicular
Technology Society, Taipei Chapter
09/22/2004
Selected as a tutorial by
IEEE MASCOT 2004
Selected as a Demo by
IEEE INFOCOM 2005
Selected as a tutorial by SPECTS 2005,
Society for Simulation, International.
Selected as an exhibition by IEEE ICC
2007, 24-28 June 2007, Glasgow, UK
Invited as a DEMO by IEEE WiVEC’08,
September 2008, Calgary, CA
Main Unique Features
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The real-world TCP/IP protocol stack is directly
used to generate accurate simulation results.
Real-world application programs can directly be
run on a simulated network:
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Realistic network traffic can be generated.
Their performances can be evaluated under
different network conditions.
The applications developed at the simulation
stage can be immediately deployed in the real
world without any change.
Main Features (2)


Using an open-system (source) architecture
to allow a researcher to easily add his (her)
own protocol modules into the simulator
Simulation methodology has been endorsed by
several journal papers (Computer Networks
2002, Computer Networks 2003, Wiley’s
Wireless Communication and Mobile Computing
2005, Elsevier’s Simulation Modeling: Theory
and Practice 2007), two book chapters
published by Nova Science Publisher 2006 and
2008, and two conference papers (IEEE
INFOCOM’99, WiVEC’08).
Network Simulation
Capabilities
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NCTUns 2.0 can simulate Ethernetbased fixed IP networks, 802.11 (b)
wireless LANs, mobile ad hoc networks,
GPRS cellular networks, optical
networks (circuit-switching and optical
burst-switching), Diffserv QoS networks
etc.
NCTUns can function as an emulator, too! (See
Chapter 7 of this book ISBN: 1-59454-830-7)
Architectures
Eight Components
Applications
Daemons
Coordinator
Protocol Modules +
Simulation Engine
Kernel Patches (Fedora 9.0 Linux 2.6.25)
Simulation Server
GUI
Client
Job
Dispatcher
Distributed Architecture
Simulation
Server
Paris
Dispatcher
Tokyo
NCTU,
Taiwan
Simulation Service Center
Boston
GUI
Client
Open-System Architecture
Protocol modules
Module API
Simulation Engine
User-level Simulator
Main GUI Components

Topology editor
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Node editor
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Specify a node’s protocol stack
Performance monitor
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Draw a network topology
Monitor and plot performance curves
Packet animation player

Playback packet transfer animation
Topology Editor
Node Editor
Performance Monitor
Packet Animation
Player
NCTUns 3.0 New Features
IEEE 802.11(b) Dual-Radio
Wireless Mesh Networks
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Each access point has two interfaces
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One operates in the infrastructure mode serving
standard IEEE 802.11(b) client stations
The other operates in ad hoc mode used to
wirelessly forward packets among access points.
Low deployment cost, high reliability
Example:

The wireless mesh network deployed in Taipei is
an IEEE 802.11(b) wireless mesh network with
8,000 mesh access points.
Client
Mesh Access Point
IEEE 802.11(e) QoS Wireless LAN
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
Provide QoS guarantee for IEEE
802.11(e) client stations.
The IEEE 802.11(e) access point polls
each associated IEEE 802.11(e) client
station to give them enough transmit
opportunities to meet their bandwidth
requirement.
IEEE 802.11(e) Access Point
IEEE 802.11(e) Client
Tactical and Active Mobile Ad Hoc
Networks
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Can be used to study future combat system
(FCS) or any active mobile ad hoc network
where mobile nodes can actively and
dynamically change their moving behaviors
according to the current environment
conditions or after receiving a command from
other mobile nodes.
Thales Group Inc. (a security and defense
company, with 60,000+ employees worldwide)
has purchased two NCTUns commercial
licenses for their military projects.
Target node
Chasing node
Directional Antennas
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Researches about networks using directional
antennas have become increasingly popular.
Support 3dB beamwidth 60-degree and 120degree directional and steerable antennas.
Use more realistic antenna gain patterns precomputed and stored in tables to compute
the received power of a packet.
Antennas can rotate or be set to point to a
particular direction.
Can increase transmission range, reduce
signal interference, and provide security.
Antenna Gain Patterns
NCTUns 4.0 New Features
IEEE 802.16(d) WiMAX Networks
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Both the PMP and mesh modes are supported.
Complete implementation of the standard
specifications
Simulation results have been validated
against mathematical theoretic results.
Two conference papers have been published
using this tool.
Many people in the world have sent emails to
us asking to use this tool for their WiMAX
researches.
WiMAX PMP mode
WiMAX mesh mode
DVB-RCS Satellite Networks
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Support DVB-RCS GEO satellite
networks
Complete implementation of the
standard specifications
Simulation results have been validated
against mathematical theoretic results.
European Space Agency would like to
use this tool for its research projects.
DVB-RCS
Basic Network
DVB-RCS
Extended Network
ITS Wireless Vehicular Networks
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Researches on wireless vehicular networks have
become increasingly popular (e.g., VANET, WiVEC,
V2VCOM conferences, etc.)
NCTUns is the first (only) simulator in the world that
tightly integrates network and traffic simulation.
NCTUns supports V2V and V2I capabilities.
NCTUns will be used by Telcordia Technologies Inc.
for a EU IVC (inter-vehicle communication) project:
EU F-7 Call-2
NEC Europe Inc. wants to use NCTUns for their EU
projects and introduce NCTUns into the EU ITS
standardization meetings.
Construct a road network
Select car profile &
Deploy car on the road
Multi-interface Mobile Node
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Nowadays a mobile device is equipped with
multiple heterogeneous wireless interfaces.
This allows it to use the most cost-effective
network to connect to the Internet.
Many related research topics have emerged:
Handover, multi-homing, trunking, etc.
Other than NCTUns, very few (if there is any)
network simulators provide this capability.
In NCTUns, a multi-interface node is
equipped with (1) 802.11(b) ad hoc mode ,
(2) 802.11(b) infrastructure mode, (3) GPRS,
and (4) DVB-RCST satellite interfaces.
Multi-interface Car
Multi-interface Mobile Node
Create multiple sockets each
bound to an interface’s IP address
NCTUns 5.0 New Features
IEEE 802.11(p)/1609 Wireless
Vehicular Networks
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Wireless vehicular network research is
becoming more and more popular.
IEEE VTS defines IEEE 802.11(p)/1609
standards for this type of networks.
NCTUns is the first network simulator that
provides supports for IEEE 802.11(p)/1609
network simulations.
For this reason, IEEE WiVEC 2008
conference (supported by IEEE VTS)
invited Prof. Wang to demo NCTUns in its
demo session.
OBU
OBU
RSU
OBU
IEEE 802.16(e) Mobile WiMAX
Networks
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Recently, IEEE 802.16(e) Mobile WiMAX
has become more popular than IEEE
802.16(d) fixed WiMAX.
Complete implementation of the
standard specifications
Simulation results have been validated
against mathematical theoretic results.
Can work with Mobile IP protocol to
roam across different IP subnets.
30+ Realistic Wireless Channel
Propagation and Fading Models
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Realistic wireless channel propagation
and fading models are very important in
generating high-fidelity simulation
results.
Over 30 channel models for various
wireless and mobile environments are
provided.
They can be easily chosen/replaced in
the GUI.
Parallel Simulations on Multicore Machines
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Recently, multi-core machines have been
popular on the market.
Performing parallel simulations on these
cores to speed up simulations is highly
desired.
Currently, NCTUns supports parallel
simulations for fixed networks.
Parallel simulations for wireless networks
will be supported in the next version.
Simulation Methodology
Novel Simulation Methodology

Use a kernel re-entering technique (invented
by Prof. Wang in 1999) to provide two
advantages:

Use real-life protocol stacks to simulate networks

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All existing real-life application programs can
directly run on a simulated network
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 simulation results are more accurate.
 can test the performance of any real-life application
program and generate realistic network traffic.
These advantages cannot be easily achieved
by traditional network simulators such as
OPNET modeler and ns-2.
Idea Was Inspired from the lo0
Loopback Interface
Suppose that we want to simulate the
following basic network:
stcp
1.0.1.2
Host 1
rtcp
Host 2
Subnet = 1.0.1
1.0.1.1
1.0.1.2
Actually stcp and rtcp Can Be
Run on the Same Machine
stcp
rtcp
127.0.0.1
User level
Kernel level
Host
lo0
127.0.0.1 (The IP address assigned to
the loopback interface)
Actually These Two Slides Differ
Very Slightly
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The used network applications are the same.
The used TCP/IP protocol stacks are the same.
The only difference is in the used links:
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
The real-life physical link vs. the loopback memory
link
If we can intercept packets so that they are
not looped back automatically, we can direct
them to our simulation engine. This way, the
simulation engine can simulate their
transmission time and their signal propagation
delay over the link.
This is the idea of this simulation methodology!
(a)
TCP_sender
Host 1
Link 1
TCP_receiver
Link 2
(b)
Virtual Link 1
TCP
sender
Virtual Link 2
Read
1999 version
Host 2
Simulation engine
Write
TCP
receiver
user-level
Kernel
TCP/IP
stack
Tunnel
interface 1
TCP/IP
stack
Tunnel
interface 2
This
is why
we interfaces
claim (1) all
We use
tunnel
to real-world
replace lo0application
interface. This
programs
canintercept
be run and
(2) the
real-world
TCP/IP
way, we can
packets
and
direct them
into
protocol
stack is
directly used.
the simulation
engine.
TCP Receiver
TCP Sender
Link 1
Host 1
Simulation Engine
ARP
ARP
PSBM
PSBM
802.3
802.3
PHY
PHY
TCP
sender
Host 2
Current version
Various protocol
modules now can be
flexibly added to the
simulation engine.
TCP
receiver
User-level
Kernel
TCP/IP
stack
TCP/IP
stack
Tunnel
interface 1
Tunnel
interface 2
A Configuration Example
rtcp
stcp 1.0.3.2
1
1.0.3.1
tun1
tun2
1.0.3.2
2
Configuration commands:
Assuming 1.0.3.X is the subnet.
ifconfig tun1 1.0.3.1
ifconfig tun2 1.0.3.2
route add 1.0.3.2 –interface tun1
route add 1.0.3.1 –interface tun2
A Route Conflict Problem
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

The simulation methodology presented so far
works very well for a single-hop network.
However, we will encounter a route conflict
problem when the network is extended to
multi-hops.
This is because we use only one machine to
simulate all routers and store their routing
entries together.
Problem Example
1
1.0.3.1
tun1
tun2
1.0.3.2
route add 1.0.3.2 –interface tun1
route add 1.0.4.1 –interface tun1
route add 1.0.4.2 –interface tun1
2
1.0.4.1
tun3
tun4
1.0.4.2
route add 1.0.3.1 –interface tun2
route add 1.0.4.2 –interface tun3
Stored Together
route add 1.0.4.2 –interface tun1
route add 1.0.4.2 –interface tun3
Conflict!
3
S.S.D.D IP Address Scheme



We solve this problem by internally using the
S.S.D.D IP address scheme for an application
to send its packets to its destination node.
The meaning of S.S.D.D. is SrcSubnetID .
host#onSrcSubnet . DstSubnetID .
host#onDstSubnet.
However, a NCTUns user need not know and
use this strange scheme. He (she) can still
use the normal 1 . 0 . subnetID . host#
address scheme. The kernel hides all the
details.
The S.S.D.D Scheme to Solve
the Route Conflict Problem
stcp 3.1.3.2 1.0.3.1
tun1
1
route add 3.1.3.2 –interface tun1
route add 3.1.4.1 –interface tun1
route add 3.1.4.2 –interface tun1
rtcp
tun2
1.0.3.2
route
route
route
route
add
add
add
add
2
3.2.3.1
3.2.4.2
4.1.3.1
4.1.4.2
1.0.4.1
tun3
tun4
1.0.4.2
–interface
–interface
–interface
–interface
3
tun2
tun3
tun2
tun3
Stored Together
route add 3.1.4.2 –interface tun1
route add 3.2.4.2 –interface tun3
route add 4.1.4.2 –interface tun3
No conflict Now!
Product Status
Product Was First Released on
November 1, 2002
Download Web Site Is Here
http://NSL.csie.nctu.edu.tw/nctuns.html
As of Oct. 22 2008, more than 12,747 people from
128 countries have registered and downloaded
this tool since its release on November 1, 2002.
Distribution of the nationality of
NCTUns registered users
(up to 2008/10/04)
1713
4321
26
87654
9
10
11
13
27
26
15
17
18
20
21
22
23
24
26
30
343028
37 35
4038
41
45
45
48
48
4951 52
52 64
55 61
70
70
101
94
101
126 165
170
140
1878
1275
960
421
236
278
240
321
297
425
Taiwan
India
U.S.A
Germany
Italy
Brazil
China
Spain
France
United Kingdom
Korea
Australia
Canada
Malaysia
Colombia
Poland
Greece
Japan
Pakistan
Romania
Hong Kong
Portugal
South Africa
Belgium
Mexico
Indonesia
Thailand
Switzerland
Turkey
Russian Federation
Sweden
Czech
Slovakia
Netherland
Ecuador
Argentina
Singapore
Venezuela
Vietnam
NCTUns 國內下載使用者學校分佈(2008/10/04之前)
3
333
43 3
111
3
1
2
4
22
2
3
4
4
4 5 45 4
6
6 66 8
7 88
8
98 9
10 9 9
12 12
12 12
248
573
12
14
15
19
20 23
24
97
87
26 28 30
26
29 32
31
38 40 48 48
57
交通大學(NCTU)
台灣大學(NTU)
台灣科技大學(NTUST)
中正大學(CCU)
成功大學(NCKU)
政治大學(NCCU)
清華大學(NTHU)
中央大學(NCU)
雲林科技大學(YUNTECH)
淡江大學(TKU)
元智大學(YZU)
中原大學(CYCU)
逢甲大學(FCU)
中山大學(NSYSU)
東華大學(NDHU)
台北科技大學(NTUT)
朝陽科技大學(CYUT)
大同大學(TTU)
海洋大學(NTOU)
長庚大學(CGU)
中興大學(NCHU)
工研院電腦與通訊研究所
輔仁大學(FJU)
義守大學(ISU)
高雄應用科技大學(KUAS)
高雄第一科技大學(NKFUST)
師範大學(NTNU)
大葉大學(DYU)
靜宜大學(PU)
明新科技大學(MUST)
東海大學
屏東商業技術學院(NPIC)
玄奘大學(HCU)
彰化師範大學(NCUE)
國立台南大學(NUTN)
康寧資訊管理(KNJC)
華梵大學(HFU)
中華大學(CHU)
樹德科技大學(SHU-TE)
銘傳大學
真理大學(AU)
東吳大學(SCIU)
國立聯合大學
立德管理學院
慈濟技術學院
國防大學
中央研究院(SINICA)
國立蘇澳海事水產學校
台北大學(NTPU)
虎尾科技大學
聖約翰技術學院(SJSMIT)
長榮大學(Chang Jung)
龍華科技大學(LHU)
暨南大學(NCNU)
興國管理學院(HKU)
嘉義大學
南台科技大學
NCTUns users are all over the world.
Dear NCTUns developers,
I'm a university professor teaching computer networks.
I've recently discovered your simulator, and I like it
so much that I've discontinued my (expensive) OPNET
Modeler license as I plan to use NCTUns in my
network design class.
Many emails have arrived
praising NCTUns or asking
Thanks a lot in advance.
how to purchase NCTUns.
With my best regards,
-- Cosimo Anglano
==================================
Prof. Cosimo Anglano
Dipartimento di Informatica
Universita' del Piemonte Orientale
15100 Alessandria, Italy
Dear Prof. Wang,
We have been very impressed by NCTUns and many of its
amazing capabilities! The simulation-emulation integration
capabilities are quite remarkable. We have been quite
impressed with the design of the GUI interface. We are
going to be demo-ing NCTUns to another network analysis
software development group within our company to show
them some of the exciting features of NCTUns.
Zeke Weeks
Consulting Services Specialist
AT&T Government Solutions, Inc.
Suite 5077
NCTUns’s emulation and GUI
1900 Gallows Road
capabilities are highly
Vienna, VA 22182
appreciated by AT&T experts.
Email: [email protected]
NCTUns Is Compared with Other WorldFamous Network Simulators
Dartmouth
Cornell
UIUC
Data source: IEEE
Communication
Magazine, July
2006 Issue
NCTU
USC
Budapest
UC
Berkeley
Concluding Remarks
Concluding Remarks




NCTUns 5.0 now is a high-quality
professional network simulator and emulator
with many unique advantages over
traditional ones.
Based on users’ feedback, we are still
continuing to improve NCTUns.
What new features should be included in
NCTUns 6.0?
You are very welcome to tell me …
Thank you.
Q&A…