La Piattaforma
LABNET per il
Telelaboratorio
___________
LABNET:
A Telelaboratory Platform
Oreste Andrisano
Franco Davoli
Luigi Paura
Stefano Vignola
Sandro Zappatore
Bologna 25 Febbraio 2004
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.
Application fields
Telecommunication systems
measurement & testing
User Classes
Research
Educational
High School
SME
University
Telecommunication
networks measurements &
testing
Other application
fields in engineering and
physics
Bologna 25 Febbraio 2004
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
Main Achievements
Technical and Methodological Aspects
 Development of
 the drivers for the control of the instrumentation
 the “Experience Manager”
 the Labnet Server
 the End-User Interfaces (GUI)
 Design and set-up of
 the Experiences
 the related Documentation
Bologna 25 Febbraio 2004
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
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
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
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
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
INTERNET
Bologna 25 Febbraio 2004
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
Reflecting the requirements in the implementation
Server side
Other
Laboratories
Telecommunication
Measurement
Testbed
Network
Measurement
Testbed
INTERNET
LABNET SERVER
Network Measurement
System Control Module
Telecommunication
Measurement System
Control Module
Other Laboratories
Interaction Module between
Network and Telco.
Measurement System
Authentication
Multicasting
Resource
Management
Protocols
Experiences
Registration
Bologna 25 Febbraio 2004
Client/Server Architecture
Data Flow Diagram
Browser
HTML
Get <HTML Page>
Send <HTML Page>
Web Server
Send Applet
Applet
Send <Command>
Send <Result>
Host Client
LABNET
Data Server
LABNET Server
Bologna 25 Febbraio 2004
Labnet Server Architecture
Labnet Server Protocol
Multicasting
Internet Suite
Protocols
Front-end Server
Bridge
Data Repository
Experience Manager
Experience Manager
Labview VI
Daemon
Vi2 Vi3
Agents
WINDOWS
TLC Measurement Testbed
Function Generator Oscilloscope Spectrum Analyzer
Scripts
LINUX
Router
Networking Testbed
Matrix
PC
Labnet Server Architecture
Experience Manager
LNS
Experience Manager
Experience IDs,
variables
Device IDs,
Commands/Results
Testbeds
Bologna 25 Febbraio 2004
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
Experience Manager
Bologna 25 Febbraio 2004
Labnet Server Architecture
Format of a LNS Packet
1
LSNP
Header
(24 bytes)
(max. 4056 bytes)
Container
Header
(16 bytes)
Container Payload
(max. 4056 bytes)
4
5
Timestamp (Sec)
Sequence Number
Packet Length
Total element
Total element 2
6
7
EXP #
Frag #
elem type
Pack
type
Total element2
bytes
tot. frag.
Number of
command containers
remote port
Variable Name
ACTUAL DATA OF THE MENTIONED VARIABLE
Total element
8
Timestamp (microsec.)
….. Variable Name (cont)
(16 bytes)
Container Payload
3
elem type
Variable Name
….. Variable Name (cont)
ACTUAL DATA OF THE MENTIONED VARIABLE
As many containers as specified by
the related field in the LSNP Header
Container
Header
2
Bologna 25 Febbraio 2004
Labnet Server Architecture
The Main Loop
LNS
Start
Repository
Hash table of
variables
Descriptors of
the experiences
Main Configuration
List of the
connected stations
Initialization of all
the lists, tables and
internal structures
Internal ACLs
Client
domain
Exp.
Manager
domain
Decode packet and
related containers
(if present)
Open network
sockets
UDP or TCP
Packet
Wait for a
Packet
According to the
LSP, prepare an
answer and send it
to clients or
exp. manager
Bologna 25 Febbraio 2004
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
Initialize Equipment 1
Initialize Equipment 2
Equipment 1 successfully initialized
Equipment 2 successfully initialized
…….
…….
Initialize Equipment M
Testbeds
Equipment M successfully
initialized
Bologna 25 Febbraio 2004
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
get_default_value_var 2
Let default_value_var 1 = x
Let default_value_var 2 = y
get_default_value_var M
Let default_value_var M = z
…..
…..
Testbeds
Bologna 25 Febbraio 2004
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
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
Telecommunication Measurement Testbed
Bologna 25 Febbraio 2004
Network Measurement Testbed
AAC-3 Kentrox
AAC-3 Kentrox
SD
SD
SD
SD
XMT
PCMCIA
SLOT
DS-3(1)
SD
XMT
DS-3(1)
XMT
SD
V.35/
EIA-530
(1)
V.35/
EIA-530
(1)
RCV
V.35/
EIA-530
(2)
SD
XMT
PCMCIA
SLOT
RCV
SD
!
DS-3(1)

ADCKentrox
RCV
SD
SD
SD
V.35/
EIA-530
(2)
DS-3(1)
SD
XMT
DS-3(1)
XMT
SD
V.35/
EIA-530
(1)
SD
V.35/
EIA-530
(1)
Cisco 3640
!

ADCKentrox
xxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxx
RCV
RCV
RCV
V.35/
EIA-530
(2)
V.35/
EIA-530
(2)
MADE IN USA
V.35/
EIA-530
(3)
V.35/
EIA-530
(3)
DSX-1
(4)
DSX-1
(4)
V.35/
EIA-530
(3)
Cisco 3620
Cisco3600
SD
CISCOS YSTEMS
Cisco 3620
Cisco 3600SERIES
SD
CISCOS YSTEMS
Cisco 3600SERIES
SERIES
xxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxx
r
MADE IN USA
RJ-45
V.35/
EIA-530
(3)
RJ-45
WARNING
DO NOT REMOVE
THIS CARD WITH
SYSTEM POWERED
10021
EXTENSION
MODULE
CISCOSYSTEMS
DS-3(1)
10300
SINGLE PORT
DS 3
10300
SINGLE PORT
DS 3
10300
SINGLE PORT
DS 3
10303
TRI-V.35/EIA-530
SINGLE DSX-1
10303
TRI-V.35/EIA-530
SINGLE DSX-1
WARNING
DO NOT REMOVE
THIS CARD WITH
SYSTEM POWERED
10021
EXTENSION
MODULE
!
DSX-1
(4)
10300
SINGLE PORT
DS 3
10300
SINGLE PORT
DS 3
10300
SINGLE PORT
DS 3
10303
TRI-V.35/EIA-530
SINGLE DSX-1
FE
DSX-1
(4)
10303
TRI-V.35/EIA-530
SINGLE DSX-1
FE
!
FE
FE
FE
Serial Local Control
FE
FE
CISCOS YSTEMS
Cisco 3600SERIES
FE
SD
Catalyst 3500
SERIES XL
FE
FE
FE
SD
PWR
SD
Cisco 7500
CISCO
Cisco 2620
Catalyst 3524-XL
SERIES
SYSTEMS
POWER
A
POWER
B
NOR MAL
Modem
Traffic Generator
Stations
Cisco 7513
Bologna 25 Febbraio 2004
SD
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
“Telecommunication Measurement Testbed”
Examples of Available Experiences
Radio Links and Modems
Satellite
Synthesis of Digital
Band-Pass Modulation
Systems via DSPs
Measurements on Nortel
Dasa equipment (with or
without emulated satellite
link)
(BFSK, BPSK, QPSK,
WCDMA…)
Multipath ISI (2- or 3-ray
channel)
Measurements of noise effect
on H.261 and MPEG coding
(with emulated satellite link)
Other Measurements (High
School - University)

Active filtering
Fine-tuning of a free FM
oscillator

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
“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 besteffort 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
Performance Evaluation
In Bytes/s - link 128 kbps
In Bytes/s - link 640 kbps
50 KB
Bytes/s
40 KB
30 KB
20 KB
10 KB
KB
0
60
120
180
time
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
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
Future Developments
From the current situation …
Networking Testbed
Remote users
CNIT
WAN
Labnet Server
The “Device Under Test” (DUT)
and the Instrumentation of each
Testbed are in the same location
INTERNET
Telecommunication
Systems Testbed
Capua Wind
Tunnel
Remote
users
Future Developments
… to Distributed Cooperative Laboratories (EUROLABNET)
DUT
Control
Network
DUT
User
Measurement
Network
Labnet (GRID)
Server
Instrumentation
and
DUTs
are distributed
over the
various Labs
involved
in the
experiment
Thanks to
Luigi Battaglia
Gianluca Massei
Amedeo Scarpiello
Nunzia Ristaldi
Alfonso Vollono
Antonio Iudici
Marta Pasi
Giuseppe Spanò
Davide Vicedomini
Andrea Zinicola
….. And also to
Nicola De Lorenzo
Piergiulio Maryni
Gianmarco Romano
Luigi Di Fraia
Umberto Pallotta
Bologna 25 Febbraio 2004
TX1
RX1
Sistema radio digitale CTR 210 HD/7
Siemens Telecomunicazioni S.p.A. (MI)
DATA IN
Probe IF out
• Segnale banda base:
8448 kbps
IF out
• Banda Radio Frequenza: 7,125 – 7,425 GHz
Probe RF out
RF out
RX2
RF in
LO
• Frequenze Intermedie:
231 MHz (Tx), 70 MHz (Rx)
• Codice:
HDB3/NRZ
• Modulazione/codifica:
16 TCM (Trellis Code Modulation)
DATA OUT
• Decodificatore di Viterbi con quantizzazione soft a 3 bit
IF in
• Traffico equivalente a 128 canali telefonici
• Ridondanza per rivelazione e correzione degli errori (FEC)
A
B
CKS
• Due canali di servizio a 64 Kb/s
– 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
Segnale a
231 MHz
Probe IF out
MIXER
Data out Data in
Portante
Fqz. : 301 MHz
Level : 5 dBm
IF out
LO
Probe RF out
Segnale a
70 MHz
NOISE GENERATOR
RF out
RX
RF in
DATA OUT
FC
: 70 MHz
SPAN : 10 MHz
IF in
A
B
Directional
Coupler
SPECTRUM
ANALYZER
CKS
TELEMISURA via HTTP
Server
WEB SERVER
Client
CODICE JSP
Applets JAVA
DataSocket
SERVER
PC
BROWSER
INTERNET
LABVIEW
GPIB Board
HTML
Applets
JAVA
Server
CNIT NAPOLI
BANCO DI MISURA
Client
REMOTIZZAZIONE DEL BANCO DI
MISURA RISPETTO AL WEB SERVER
Server
PC
WEB SERVER
BROWSER
HTML
Applets
JAVA
CODICE JSP
INTERNET
Applets JAVA
PC
DataSocket
SERVER
CNIT
PARMA
LABVIEW
GPIB Board
BANCO DI MISURA
CNIT
NAPOLI
AMPLIAMENTO DEL BANCO DI MISURA:
Diagramma ad occhio – Costellazione TCM
DATACOM/TELECOM
ANALYZER
TX
Pattern di bit a 8 Mb/s
DATA IN
RF SIGNAL GENERATOR
MIXER
Segnale a
231 MHz
Probe IF out
Data out Data in
Portante
Fqz. : 301 MHz
Level : 5 dBm
IF out
Probe RF out
LO
Segnale a
70 MHz
NOISE GENERATOR
SPECTRUM
ANALYZER
FC
: 70 MHz
SPAN : 10 MHz
RF out
RX
RF in
DATA OUT
IF in
Directional
Coupler
OSCILLOSCOPE
COSTELLAZIONE
DIAGRAMMA
TCM
16 STATI
AD OCCHIO
TRA 1 TRA 2
A
B
CKS
TRIGGER