Presentazione di PowerPoint

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La Piattaforma LABNET per il Telelaboratorio _____
______ LABNET A Telelaboratory Platform
Oreste Andrisano Franco Davoli Luigi
Paura Stefano Vignola Sandro Zappatore
Bologna 25 Febbraio 2004
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MAIN GOALS
To develop a H/W and S/W architecture for the
remote control of distributed real laboratory
equipment at various complexity levels.
To offer access to the physical resources on the
basis of different users needs, skills and
fields.
Bologna 25 Febbraio 2004
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LABNET-Methodologies
Development Guidelines

• Design of the Software Architecture and
  development of LABNET Server and Client sides
• Design and set-up of experiments on the
  Telecommunication Measurement Testbed
• Design and set-up of experiments on the
  Networking Testbed
• Definition of interfaces for the interconnection
  of external laboratories (e.g., CIRA wind tunnel)

Bologna 25 Febbraio 2004
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Main Achievements
Technical and Methodological Aspects

• Development of

• Design and set-up of

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Main Achievements
Scientific Aspects
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Why a specific Software Architecture

• Heterogeneity of physical interfaces and
  communication protocols
• Each class of instruments is characterized by a
  specific physical interface and communication
  protocol for the remote access to the equipment.

• Heterogeneity of development environments
• In general, each class of instruments is provided
  with a specific software development kit for data
  gathering and reporting (e.g., LabView for
  oscilloscopes, voltmeters, etc., HP-Openview for
  routers, etc.)

Bologna 25 Febbraio 2004
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Why a specific Software Architecture

• Heterogeneity of the access technologes
  The system
  must allow an efficient use of the laboratories
  by users exploiting different types of access
  technology (e.g., ISDN, xDSL, leased lines, )

• Educational Sessions often involve a great
  number of user stations
• The multimedia streams with the information
  produced by the instruments and by network and
  telecommunication facilities must reach the
  student stations in an efficient way (without
  waste of transmission resources)

• Access management
• The system must be able to allocate the proper
  resources for each requested experience, thus
  avoiding conflicts among different users

Bologna 25 Febbraio 2004
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Why a specific Software Architecture

• GUI suitably designed for the ILS mission

• The attention of the users should be focused on
  the specific features of the experiment being
  performed
• Only a subset of the instruments front panel
  controls is actually reproduced on the client
  side, according to the specific experiment, the
  depth of the experience and, possibly, the users
  skills
• The GUI allows to reproduce more than one device
  on the same page, thus providing a unified view
  of the set-up ready to be used, rather than a
  mere group of instruments.

Bologna 25 Febbraio 2004
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Reflecting the requirements in the
implementation Client side
Lecturer/Instructor station

• Two different client stations

Student station

• To connect to the laboratory environment, only a
  generic browser with Java2 plug-in is needed

To the LABNET Server
Remote users
Bologna 25 Febbraio 2004
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Reflecting the requirements in the
implementation Client side
selects and initializes the desired experience
fully controls the virtual devices involved in
the experience

• Lecturer Station

monitors the presence of the student stations
delegates the control of the experience to a
specific student station
communicates with LNS by using unicast packets
(TCP)
passively participates in the experience, showing
the user the current state and values of the
virtual devices

• Student Station

receives data from LNS by means of multicast
packets
communicates with LNS by using unicast packets
whenever designated by the lecturer
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Reflecting the requirements in the
implementation Server side
Bologna 25 Febbraio 2004
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Client/Server Architecture
Data Flow Diagram
Get ltHTML Pagegt
Send ltHTML Pagegt
Send Applet
Send ltCommandgt
Send ltResultgt
LABNET Server
Host Client
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Labnet Server Architecture
Labnet Server Protocol
Internet Suite Protocols
Multicasting
Front-end Server
Bridge
Data Repository
Experience Manager
Experience Manager
WINDOWS
LINUX
Labview VI
Vi2
Vi3
Daemon
Agents
Scripts
TLC Measurement Testbed
Networking Testbed
Spectrum Analyzer
Router
Matrix
PC
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Labnet Server Architecture
Experience Manager
LNS
Experience IDs, variables
Experience Manager
Device IDs, Commands/Results
Testbeds
Bologna 25 Febbraio 2004
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LNS Communication Protocol
Labnet Server Architecture

• LNSP is an ad-hoc communication protocol for
  data transfer between LNS and Experience Manager.
• The Protocol Data Unit consists of a header
  (referring to a specific experience) and zero,
  one, or more data containers
• The data container is a structure for the
  variable (scalar or vector) encapsulation.
• LNSP exploits the Internet suite for the actual
  exchange

LNS
LNSP
TCP/IP
TCP/IP
LNSP
Experience Manager
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Labnet Server Architecture
Format of a LNS Packet
bytes
1
2
3
4
5
6
7
8
Timestamp (Sec)
Timestamp (microsec.)
Number of containers
Pack type
Sequence Number
EXP
command
Packet Length
Frag
tot. frag.
remote port
As many containers as specified by the related
field in the LSNP Header
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Labnet Server Architecture
The Main Loop
LNS
Start
Repository
Descriptors of the experiences
Main Configuration
Hash table of variables
List of the connected stations
Initialization of all the lists, tables and
internal structures
Internal ACLs
Open network sockets
UDP or TCP Packet
Client domain
Decode packet and related containers (if present)
Wait for a Packet
According to the LSP, prepare an answer and send
it to clients or exp. manager
Exp. Manager domain
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An example initialization (1)
Labnet Server Architecture
LNS Communication Protocol
Launch the experience N
LNS
Initialize the experience N
Experience N successfully initialized
Experience Manager
Initialize Equipment 1
Equipment 1 successfully initialized
Equipment 2 successfully initialized
Initialize Equipment 2
.
.
Equipment M successfully initialized
Initialize Equipment M
Testbeds
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Labnet Server Architecture
LNS Communication Protocol
An example initialization (2)
LNS
Experience Manager
get_default_value_var 1
Let default_value_var 1 x
get_default_value_var 2
Let default_value_var 2 y
..
..
get_default_value_var M
Let default_value_var M z
Testbeds
Bologna 25 Febbraio 2004
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Labnet Server Architecture
LNS Communication Protocol
An example initialization (client side)
Master Station
Java Applet

• Experience N ready
• Launch the specific applets
• Display the default values of variables

Select the experience N
LNS
Initialize the experience N
Experience N successfully initialized
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Labnet Server Architecture
The actual communication
Java Applet
LNS
Experience Manager
Testbeds
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Telecommunication Measurement Testbed
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Network Measurement Testbed
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External Laboratories

• CIRA Wind Tunnel in Capua
• Connected via HDSL at 2 Mbps
• Measurement of total pressure loss on
  bi-dimensional model in wind tunnel CT1
• All main parameter setting remotely controllable
  and measurement displayed

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Telecommunication Measurement Testbed Examples
of Available Experiences
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Networking Testbed Examples of Available
Experiences
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Performance Evaluation
Measured traffic vs time during the session
related to an experiment on analog modulation.
The client is connected to the server via a
transmission line at 640 kbps (dotted line) and
at 128 kbps (solid line).
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Evaluation of educational impact
Serveral experiences have been tested in both
university and high school settings. In
particular
Training courses for the Ministry of
Communications Educational Project
DIST Università di Genova Classes in
Telecommunication Networks, Telematics, Digital
Communications
ITIS Augusto Righi - Napoli
ITIS Maserati - Voghera
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Future Developments
From the current situation
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Future Developments
to Distributed Cooperative Laboratories
(EUROLABNET)
DUT
DUT
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Thanks to
Bologna 25 Febbraio 2004
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Sistema radio digitale CTR 210 HD/7 Siemens
Telecomunicazioni S.p.A. (MI)
TX1
RX1
DATA IN
Probe IF out

• Segnale banda base 8448 kbps
• Banda Radio Frequenza 7,125 7,425 GHz
• Frequenze Intermedie 231 MHz (Tx), 70 MHz (Rx)
• Codice HDB3/NRZ
• Modulazione/codifica 16 TCM (Trellis Code
  Modulation)

IF out
LO
Probe RF out
RF out
RX2
RF in
DATA OUT

• Decodificatore di Viterbi con quantizzazione
  soft a 3 bit
• Traffico equivalente a 128 canali telefonici
• Ridondanza per rivelazione e correzione degli
  errori (FEC)
• Due canali di servizio a 64 Kb/s

IF in
A
B
CKS
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BANCO DI MISURA Maschera di emissione a
frequenza intermedia e BER
DATACOM/TELECOM ANALYZER
TX
Pattern di bit a 8 Mb/s
RF SIGNAL GENERATOR
DATA IN
MIXER
Data out
Data in
Segnale a 231 MHz
Probe IF out
Portante
Fqz. 301 MHz Level 5 dBm
IF out
Segnale a 70 MHz
LO
Probe RF out
NOISE GENERATOR
RF out
RX
RF in
SPECTRUM ANALYZER
Directional Coupler
DATA OUT
IF in
FC 70 MHz SPAN 10 MHz
A
B
CKS
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TELEMISURA via HTTP
Server
WEB SERVER
Client
CODICE JSP
Applets JAVA
DataSocket SERVER
PC
LABVIEW
INTERNET
BROWSER
GPIB Board
HTML
Applets JAVA
Server CNIT NAPOLI
BANCO DI MISURA
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REMOTIZZAZIONE DEL BANCO DI MISURA RISPETTO AL
WEB SERVER
Client
Server
PC
WEB SERVER
BROWSER
HTML
CODICE JSP
Applets JAVA
INTERNET
Applets JAVA
PC
DataSocket SERVER
CNIT NAPOLI
LABVIEW
CNIT PARMA
GPIB Board
BANCO DI MISURA
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AMPLIAMENTO DEL BANCO DI MISURA Diagramma ad
occhio Costellazione TCM
DATACOM/TELECOM ANALYZER
TX
Pattern di bit a 8 Mb/s
RF SIGNAL GENERATOR
MIXER
DATA IN
Data out
Data in
Segnale a 231 MHz
Probe IF out
Portante
Fqz. 301 MHz Level 5 dBm
IF out
SPECTRUM ANALYZER
Segnale a 70 MHz
LO
Probe RF out
NOISE GENERATOR
FC 70 MHz SPAN 10 MHz
RF out
RX
RF in
Directional Coupler
DATA OUT
OSCILLOSCOPE
IF in
DIAGRAMMA AD OCCHIO
TRA 1
TRA 2
TRIGGER
A
B
CKS