1. La Piattaforma LABNET per il Telelaboratorio A Telelaboratory Platform
___________
LABNET:
A Telelaboratory Platform
Oreste Andrisano
Franco Davoli
Luigi Paura
Stefano Vignola
Sandro Zappatore
Bologna 25 Febbraio 2004

2. MAIN GOALS User Classes Application fields High School University
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.
Telecommunication systems measurement & testing
Telecommunication networks measurements & testing
Other application fields in engineering and physics
Application fields
High School
University
User Classes
Research
Educational
SME
Bologna 25 Febbraio 2004

3. 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

4. Technical and Methodological Aspects
Main Achievements
Technical and Methodological Aspects
Development of
the drivers for the control of the instrumentation
the Labnet Server
the End-User Interfaces (GUI)
the “Experience Manager”
Design and set-up of
the Experiences
the related Documentation
Bologna 25 Febbraio 2004

5. Main Achievements Scientific Aspects
Study and Design of Protocols Suitable for the proposed Integrated Learning System (ILS)
Design of a Software Architecture for the remote access and control of the Laboratory Environment
Performance evaluation of the system
Study and design of scalable audio/video coders for multimedia network applications
Evaluation of the effects of satellite link fading on the video stream quality, using different coding schemes and/or data packetization
Bologna 25 Febbraio 2004

6. 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

7. 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

8. 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 instrument’s 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

9. 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
INTERNET
Remote users
Bologna 25 Febbraio 2004

10. 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

11. Reflecting the requirements in the implementation
Server side
Network
Measurement
Testbed
Telecommunication
Other
Laboratories
INTERNET
LABNET SERVER
Multicasting
Authentication
Registration
Resource
Management
Protocols
Experiences
Network Measurement System Control Module
Telecommunication Measurement System Control Module
Other Laboratories
Interaction Module between
Network and Telco.
Measurement System
Bologna 25 Febbraio 2004

12. Client/Server Architecture
Data Flow Diagram
Browser
Get <HTML Page>
Web Server
HTML
Send <HTML Page>
Send Applet
Applet
Send <Command>
LABNET
Data Server
Send <Result>
LABNET Server
Host Client
Bologna 25 Febbraio 2004

13. Labnet Server Architecture TLC Measurement Testbed
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
Function Generator
Oscilloscope
Spectrum Analyzer
Router
Matrix PC

14. Labnet Server Architecture
Experience Manager
LNS
Experience IDs, variables
Experience Manager
Device IDs, Commands/Results
Testbeds
Bologna 25 Febbraio 2004

15. LNS Communication Protocol
Labnet Server Architecture
LNS Communication Protocol
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 è il protocollo di comunicazione sviluppato ad hoc utilizzato tra LNS e Gestore.
L’elemento di comunicazione è un pacchetto costituito da un header (che permette di identificare esperienza numero sequenza …) e da zero o più container.
Il container è la struttura utilizzata per l’incapsulamento delle variabili.
LNSP si poggia sulla suite TCP/IP
LNSP
Experience Manager
Bologna 25 Febbraio 2004

16. Labnet Server Architecture
Format of a LNS Packet 1 2 3 4 5 6 7 8
bytes
LSNP
Header
(24 bytes)
Timestamp (Sec)
Timestamp (microsec.)
Number of containers
Sequence Number
EXP #
Pack type
command
Packet Length
Frag #
tot. frag.
remote port
Container
Header
(16 bytes)
Total element
Total element 2
elem type
Variable Name
ACTUAL DATA OF THE MENTIONED VARIABLE
….. Variable Name (cont)
Container Payload
(max bytes)
the related field in the LSNP Header
As many containers as specified by
Container
Header
(16 bytes)
Total element
Total element2
elem type
Variable Name
ACTUAL DATA OF THE MENTIONED VARIABLE
….. Variable Name (cont)
Container Payload
(max bytes)
Bologna 25 Febbraio 2004

17. LNS Labnet Server Architecture The Main Loop Repository Client domain
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
Client domain
UDP or TCP Packet
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
Bologna 25 Febbraio 2004

18. An example: initialization (1)
Labnet Server Architecture
LNS Communication Protocol
An example: initialization (1)
Launch the experience N
LNS
Initialize the experience N
Experience N successfully initialized
Experience Manager
Il primo problema che il gestore deve affrontare è il controllo della disponibilità della strumentazione interessata dall’esperienza e l’inizializzazione della stessa. Per questa operazione si prevede un meccanismo descritto in maniera semplificata nell’animazione presente nel lucido corrente e nel successivo.
Initialize Equipment 1
Equipment 1 successfully initialized
Initialize Equipment 2
Equipment 2 successfully initialized
…….
…….
Initialize Equipment M
Equipment M successfully initialized
Testbeds
Bologna 25 Febbraio 2004

19. Labnet Server Architecture
LNS Communication Protocol
An example: initialization (2)
Exp_1_var 1 = x
Exp_1_var 2 = y
Exp_1_var M = z
…..
LNS
Exp1 Var 1
Exp1 Var 2
Exp1 Var N
Allocate var 1 of Exp 1 and set Exp_1_var 1 = x
Allocate var 2 of Exp 1 and set Exp_1_var 2 = y
Allocate var M of Exp 1 and set Exp_1_var M = z
…..
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

20. 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
Bologna 25 Febbraio 2004

21. Labnet Server Architecture
The actual communication
Java Applet
LNS
Exp1 Var 1
Exp1 Var 2
Exp1 Var N
Experience Manager
Testbeds
Bologna 25 Febbraio 2004

22. Telecommunication Measurement Testbed
Bologna 25 Febbraio 2004

23. Network Measurement Testbed
Bologna 25 Febbraio 2004

24. 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
Bologna 25 Febbraio 2004

25. Synthesis of Digital Band-Pass Modulation Systems via DSPs
“Telecommunication Measurement Testbed” Examples of Available Experiences
Radio Links and Modems
Satellite
Other Measurements (High School - University)
Synthesis of Digital Band-Pass Modulation Systems via DSPs
(BFSK, BPSK, QPSK, WCDMA…)
Measurements on Nortel Dasa equipment (with or without emulated satellite link)
Active filtering
Fine-tuning of a free FM oscillator
Multipath ISI (2- or 3-ray channel)
Measurements of noise effect on H.261 and MPEG coding (with emulated satellite link)
Analog Modulation AM FM
DSB spectra / effect of synchronization loss
RF Interference (Notch effect)
BER Measurements for QPSK, varying Eb/No and coding rate, with bandwidth estimation
Bologna 25 Febbraio 2004

26. “Networking Testbed” Examples of Available Experiences
Measurements on networking equipment
Routing
QoS
VoIP
Measurements at various Internet stack levels and on hetereogeneous access networks (Ethernet, ATM, Frame-Relay, … )
Building a network infrastructure based on a static/dynamic routing policy
Video streams transmission on best-effort netwoks with:
RSVP
DiffServ
QoS and P-QoS evaluation by varying the traffic load offered to the channel
Performance evaluation of different protocols
TCP congestion control with different TCP implementations (Reno, Tahoe, Vegas), varying the channel bandwidth
RIP/OSPF Routing table visualization in the presence of network topology changes
Real time measurements of
Jitter
Queue length
TCP goodput
Packet loss
Signalling trace
Bologna 25 Febbraio 2004

27. 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).
Bologna 25 Febbraio 2004

28. 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
Bologna 25 Febbraio 2004

29. From the current situation …
Future Developments
From the current situation …
INTERNET
Networking Testbed
CNIT WAN
Remote users
Capua Wind Tunnel
Labnet Server
The “Device Under Test” (DUT) and the Instrumentation of each Testbed are in the same location
Telecommunication Systems Testbed

30. are distributed over the
Future Developments
… to Distributed Cooperative Laboratories (EUROLABNET)
Control Network
DUT
DUT
Instrumentation and
DUTs
are distributed over the
various Labs involved
in the experiment
User
Measurement Network
Labnet (GRID) Server

31. Thanks to Luigi Battaglia Antonio Iudici Gianluca Massei Marta Pasi
Amedeo Scarpiello Giuseppe Spanò
Nunzia Ristaldi Davide Vicedomini
Alfonso Vollono Andrea Zinicola
….. And also to
Nicola De Lorenzo Luigi Di Fraia
Piergiulio Maryni Umberto Pallotta
Gianmarco Romano
Bologna 25 Febbraio 2004

32. 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
Probe RF out LO
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

33. Maschera di emissione a frequenza intermedia e BER
– 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

34. TELEMISURA via HTTP BANCO DI MISURA Server PC INTERNET Client
WEB SERVER
Client
CODICE JSP
Applets JAVA
DataSocket
SERVER PC
LABVIEW
INTERNET
BROWSER
GPIB Board
HTML
Applets JAVA
Server
CNIT NAPOLI
BANCO DI MISURA

35. REMOTIZZAZIONE DEL BANCO DI MISURA RISPETTO AL WEB SERVER
Client PC
Server
BROWSER
WEB SERVER
HTML
CODICE JSP
Applets JAVA
INTERNET
Applets JAVA PC
DataSocket
SERVER
CNIT
NAPOLI
LABVIEW
CNIT
PARMA
GPIB Board
BANCO DI MISURA

36. AMPLIAMENTO DEL BANCO DI MISURA:
Diagramma ad occhio – Costellazione TCM
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
SPECTRUM ANALYZER
Segnale a
70 MHz
Probe RF out LO
NOISE GENERATOR
FC : 70 MHz
SPAN : 10 MHz
RF out RX
RF in
Directional Coupler
DATA OUT
COSTELLAZIONE
TCM 16 STATI
OSCILLOSCOPE
IF in
DIAGRAMMA
AD OCCHIO
TRA 1
TRA 2
TRIGGER A B
CKS