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Bologna 25 Febbraio 2004 - Teledoc 2
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