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István Csabai Eötvös University Budapest. Network Measurement Virtual Observatory. Science : early times. observation. theory. reality. Science : past. instruments. observation. theory. reality. experiment. models. test. predictions. Science : present. instruments. observation. - PowerPoint PPT Presentation
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NETWORK MEASUREMENT VIRTUAL OBSERVATORY
István Csabai Eötvös University Budapest
observationtheory reality
Science: early times
observationtheory reality
models
experiment
instruments
test
predictions
Science: past
observationtheory reality
models
experiment
instruments
virtual realitypredictions
test
Science: present
observationtheory reality
models
experiment
instruments
virtual realitypredictions
test
Other disciplines are similar: whole genomes, satellite maps, sensor networks, etc.
To understand the complex reality, we need complex models
To verify complex models we need a lot of data (large statistical sample)
Virtual Observatories: few key elements
Modern web and database technologies to standardize and share data
Advanced indexing techniques for multi-terabyte, multidimensional archives
Distributed computing for analysis and modeling – move computation to data
Visualization Same challenges for different
disciplines: we can share the tools and solutions
Internet Although man-made but
there is no “blueprint” “Astronomical” number of
components, complex non-linear interactions
We need similar methods as in natural sciences to understand its behavior
We need to observe / experiment model
Future internet: self-aware, self-managing, self-healing …
Measurement/experiment facilities Planetlab / Onelab
A network of open computers distributed across the world and available for the development of new network services.
Realistic platform available for trial deployment and experimentation, with services such as distributed storage, network mapping, peer-to-peer systems, distributed hash tables and query processing.
OneLab2 EU Integrated Project 2008-2010 ,29 participants Europe wide + 1 from Japan, budget 7.5 M€
Measurement/experiment facilities Etomic
An open measurement infrastructure in Europe to carry out high temporal resolution (~10 nano second), globally synchronized, active measurements. Provides high resolution, spatially extended dynamic picture of fast changes in the network traffic.
ETOMIC hardware Server PC architecture, Linux Endace DAG 3.6 GE card
or ARGOS FPGA measurement card with packet sending capability (packet offset
~60 ns) GPS antenna for
global time synchronization
New low cost version based on Blackfin microcontroller dedicated IP packet time stamping module
(< μsec) Can be called as SOAP web services / from
stored procedures low cost (300 €)
Web interface: experiment bundle
Scheduling
Experiments
Time slot reservation in a calendar system for the experiments
User experiments
Science archive – based on CasJobsCasJobs: database + batch + web services(Developed for SDSS; Alex Szalay , William O’Mullane, Nolan Li, María Nieto-Santisteban, Ani Thakar, Jim Gray)
most network measurement projects:• use a single dedicated infrastructure• scan only narrow sub-segments• analyze a limited set of network
characteristics• centralized and separated from
each other
key idea: try to interconnect separate• measurement efforts
• large-scale behavior• long-term evolution
Network Measurement Virtual Observatory
Network Measurement Virtual Observatory The challenge: seamless integration of multiple tools
and data sources We need easy to use standards for data access/exchange Searchable metadata, organized access Working prototypes, use cases
Unified interface: standardized data model (NetXML) wrapper software @ each platform (to convert data into
NetXML) standardized way of reaching services (Web services)
Mediator: metadata registry service registry (e.g. time slice service) joint queries: query broker Many ideas, concepts from
astronomical VO
database
Processing functionsStored procedures
Search toolsVisualization tools
Web service
interface
graphical user interface
traceroute archive
SQL
data subset
XML, SOAP
WSDL, processed data
database
Processing functionsStored procedures
Search toolsVisualization tools
Web service
interface
graphical user interface
delay archive
SQL
data subset
XML, SOAP
WSDL, processed data
database
Processing functionsStored procedures
Search toolsVisualization tools
Web service
interface
graphical user interface
BGP archive
SQL
data subset
XML, SOAP
WSDL, processed data
Mediator/query broker
GUI
WS
Use cases: what do we measure
one way delay (60 ns resolution)
tracking topology changes available bandwidth meter transport protocol testing queuing delay tomography geolocalization …
Geolocalization
A
B
?
Geolocalization Useful for: content distribution, user identification,
network diagnostics, language selection,… WhoIS and DNS databases are not reliable Method: probabilistic triangulation from landmark
nodes More landmarks – more precise localization – more
computation
Hierarchical Triangular MeshHierarchical subdivision of spherical triangles, represented as quad tree.
Developed for indexing the sky (SDSS; A. Szalay, G. Fekete)
Standalone library + SQL Server integrationQuick routines for intersecting spherical polygons: speedup geolocalization calculations
observationtheory reality
models
experiment
instruments
virtual realitypredictions
test
Conclusion
observationtheory reality
models
experiment
instruments
virtual realitypredictions
test
Conclusion
observationtheory reality
models
experiment
instruments
virtual realitypredictions
test
Conclusion
P. Mátray, P. Hága, S. Laki, J. Stéger B. Hullár, G. Vattay (Eötvös University)
collaborations
Universidad Autonoma de Madrid Universidad Publica de Navarra Ericsson Research Tel Aviv University
This work was partially supported by the National Office for Research and Technology (NAP 2005/ KCKHA005) and the EU ICT Moment (#215225) and OneLab2 Integrated Project
(#224263).
Collaborators, acknowledgements
Sok boldog születésnapot, Sanyi!
Sándor Laki (C) IP Geolocation 31
Plans
Probabilistic geolocation Using the distribution of the velocity
of signal propagation Pre-clustering delay measurements
New kind of science: mega-surveys New technology has allowed new kind of surveys
All-sky surveys GALEX ,SDSS, IRAS,WMAP, NVSS, …
Multi-wavelength Radio, infrared, optical, UV, X-ray, Gamma-ray Gravitational waves, neutrinos & cosmic particles
Time domain Pan-STARRS, LSST, GAIA, …
Collecting data in (public) digital archives Instead of targeting special objects: observe everything New challenge: store, organize, analyze huge amount of data Virtual Observatories / E-science
main goals:• create large archives to:
share available measurement data & analysis results provide easy-to-use “online” network data analysis tools
• integrate existing measurement and monitoring infrastructures toward a common and open platform:
standardisation of network measurement data design and implement a system to share network data
store & share raw data• joint analysis of different types of measurement data• reanalysis (with new statistical methods)• reference data (historical comparison)
share analysis tools• server side processing simplifies client applicatons• no need to transfer bulk data packages: online processing
exchange data in a standardized way• existing efforts (OGF, IETF, KML)
• Network Measurement Virtual Observatory (nmVO)
Database
Web servicesnetXML
Science archive – based on CasJobs
database Web service
interface Stored procedure
Open repository