1. 1 Grid networking in EU DataGRID TERENA conference Limerick - 5 th of June 2002 Pascale PRIMET Manager of the workpackage Network of the DataGRID project INRIA/ RESO - ENS Lyon Pascale.Primet@ens-lyon.fr

2. 2 Outline The European DataGRID network High performance Grid Networking Grid Network Monitoring in EDG Network Services for the GRID Perspectives

3. 3 Grid technology The purpose of a Grid is to –aggregate a large number of resources – to build a high performance –computing and storage environment. The distributed resources may be –interconnected via a VPN – or the Internet.

4. 4 European DataGRID project The EDG project http://www.eu-datagrid.org/ aims to provide production quality testbeds, using real-world applications with real data:http://www.eu-datagrid.org/ High Energy Physics process the huge amount of data from LHC experimentations Biology and Medical Imaging –sharing of genomic databases for the benefit of international cooperation –processing of medical images for medical collaborations Earth Observations –access and analysis of atmospheric ozone data collected by satellites as Envisat-1 Calendar : january 2001 to december 2003 Funded by the European Union

5. 5 EDG - Partners CERN – France CNRS – France –Testbed (WP6) –Network (WP7) –Bio application (WP10) ESA/ESRIN – Italy INFN – Italy NIKHEF – The Netherlands PPARC - UK

6. 6 European DataGRID project 7 applications distributed among 6 virtual organisations 11 organisations over 15 countries 40 sites in Europe Based on the European GEANT backbone and National NRENs http://ccwp7.in2p3.fr

7. 7 EDG - Infrastructure

8. 8 High Performance Grid Networking Technical collaboration with Network providers –Requirement studies (Application and middleware) –Available infrastructure and services review –Enhanced Network services tests Technical collaboration with Grid users –End to end monitoring –Transport protocols studies and optimisation –E2E performances problems identification –Network cost functions realization for scheduling

9. 9 « Physical » view of a Grid Network Public Network No security No predictable performances No control on the traffic The flat INTERNET Resource = CE (computing element) or Resource = SE (storage element)

10. 10 Logical view of the Grid Network

11. 11 EDG WP7 «Network » activities Provisionning Monitoring E2E QoS and Transport Services Security Manager: Pascale Primet - INRIA/RESO – 25 persons- 2,5 funded

12. 12 EDG WP7 activities T7.1 : Technical Collaboration with Dante/NRENs –Pilot services test (QoS, multicast) –Dedicated machines in GEANT PoPs T7.2 : QoS and advanced services - QoS services test with biological/medical applications - Reliable Multicast Protocol test and deployement - High performance transport protocol (TCP/nonTCP) T7.3 : Network Monitoring Architecture –Design and deploy a Network Monitoring Infrastructure –Visualize and analyze monitoring data T7.4 : Security => EDG Security team Applications Middleware Infrastructure Management Testbed

13. 13 Collaboration with GEANT E2E : Close participation to pilot services –Test of IP Premium service/WP10 In Backbone : (our proposal) –Use of dedicated machines in GEANT POPs Amsterdam, Geneva, London –Tests of high throughput transfers –Test of IP multicast for Reliable Multicast –Sharing WP7 monitoring and DANTE monitoring data

14. 14 Network provisioning Network Requirements studies Application Requirements (WP8, WP9, WP10) Middleware Requirements Physical Networks 1.GEANT : 2.5 Gbps to 10 Gbps 2.NRENs : from 155Mbps (or less) to 2.5Gbps 3.Regional networks: from 2Mbps to 155Mbps 4.Local Area Networks : from 10Mbps to 1Gbps) Is a « Virtual Private Network » required for the DataGRID ? concept definition / VPN technologies review See our D7.1 document on WP7 EDG site

15. 15 Methodology 1 Flows 2 Logical links 3 Physical links 4 Monitoring

16. 16 Output file Application requirement studies Top down stream identification Data Server CPU Client desktop CERN CPU Client Tier 1 Tier 2 Tier 3-4 dedzdscdcdsc scsdcdscdcds Input File DatabaseProcess Binary dx cs GRID Flows list WP8WP9WP10

17. 17 Some numbers HEP applications: –Bulk Data transfer : from 100Mb/s (TB1) to 1Gb/s cont. (TB3) Medical applications: –Interactive Traffic with burst of more than 1Gbyte –Real Time High Performance Vizualisation/Simulations

18. 18 Network performances measurement (1) For Provisioning: –To be available, via visualization to human observer (user, network/system administrators) –To provide tools for network performances measurement, problems identification and resolution (bottlenecks, point of unreliability, quality of service needs, topology…) –To achieve network performance forecast and optimization – Capacity planning

19. 19 Network performances measurement (2) For Resource Brokers: –Network performance parameters are used for optimizing resource allocation (replication, MPI, Remote file access…) –Network performance metrics must be published to the Grid Information System Be accessible through aggregated functions called by Grid resource broker services (computing and data storage).

20. 20 Architectural design four functional units : – monitoring tools or sensors –a repository for collected data; –the means for data analysis to generate network metrics; – the means to access and to use the derived metrics. See our D7.2 document on WP7 EDG site

21. 21 Network Monitoring Architecture P_RTPLP_NWSMiddleware Data Collector Raw IPerfGridFTPSNMP…PingEr Sensors Repository Publication MapCenter RTPL Resource BrokerNetwork managers Data processor LDAP Forecaster Analysis

22. 22 Measurement methods Active methods –Injection of traffic inside the network for testing performances between two points –problem: may be intrusive (TCP/UDP throughput) Passive methods –Collect traffic informations in one point of the network : router, switch, dedicated passive host, computing element or storage element (GRIDftp logs)… –Problem : give network usage, not capacity

23. 23 Identify bottlenecks and real throughput availability Active measurement

24. 24 Passive measurement Passive measures at one point

25. 25 Metrics and tools Round Trip Delay => PinGER (Lyon->nikhef)PinGER Packet Loss => PinGER (Lyon->nikhef)PinGER TCP throughput => IPerfER (nikhef -> Ral)IPerfER UDP throughput => UDPMon (CZ->Cern) site connectivity => MapCenter service availability => MapCenter OneWay metrics => RIPEncc test boxes

26. 26 Some results from testbed sites to CERN –Pinger RTT: Average: 25ms –OWD: average: 9ms –OWL: average 0 to 0,3% –TCP Throughput : from 0 to 350Mb/S

27. 27 PingER results

28. 28 IPerfER Results

29. 29 Schema and LDAP backend Grid applications/mw are able to access network monitoring metrics via LDAP services according to a defined LDAP schema. LDAP back end to make measurements visible through the Globus GIIS/GRIS system has been developed. –that fetch, or have pushed, the current metric information from the local network monitoring data store. R-GMA is tested as an alternative solution to Globus MDS http://ccwp7.in2p3.fr/mapcenter

30. 30 Network Cost functions Network metrics published in LDAP repositories are used by resource brokers and replica managers through network cost functions : Time = networkCost (SE1, SE2, filesize) Computed from 1.GridFTP logs 2.TCP throughput measurements (aggregated) 3.RTT Measurements (aggregated)

31. 31 EDG Network Cost Function Network Element => Network COST function

32. 32 EDG MapCenter Tool –Connectivity of sites –Availability of services running over all sites involved –Efficient and flexible model to logically and graphically represent all communities, organization, applications running over grids. –MapCenter enables representation of any level of abstraction (national and international organizations, virtual organizations, application etc) needed by grid environments. –http://ccwp7.in2p3.fr/mapcenterhttp://ccwp7.in2p3.fr/mapcenter

33. 33 Network and Transport Services QoS: –Demonstrate and build experience in use of E2E diffserv services in Grid context –Feedback experiences to GEANT/DANTE, NRENs and LANs Transport –High performance transport protocols –Reliable multicast protocols tests

34. 34 QoS and Grid Applications 4 types of flows => Required Services –Bulk data transfer => Scavenger, AF –Interactive flows => AF, EF, ECN, others? –Real-time flows => EF, others? –Test traffic => Scavenger

35. 35 QoS and Experimental work Routers configuration : WRR, DRR… QBSS : in LAN and LFN (CERN-Caltech) ECN and TCP over ECN Alternative models: –ABE, EDS, proportional DS E2E Premium service for Medical Applications

36. 36 High Performance Transport TCP mechanisms optimization –Tests of applicability of new mechanisms Use of QoS solutions –diminution of Packet Loss –Active queue management (WRED, ECN) –TCP over DiffServ (AF, EF, PDS, EDS…) Reliable Multicast Protocol –Test and deployement of JRMS and TRAM

37. 37 Issues and perspectives Refine NetworkCost functions algorithms Scheduling of active measurements Sensor deployment scalability Automatic metrics analysis Network performances forecasting QoS services E2E availability and effectiveness Transport services deployment

38. 38 Conclusion In testbed0 and testbed1 the networking functionality was here – IP technology: Best effort –GEANT has been deployed –A Performance Measurement Architecture developed In testbed 2 and testbed 3 –Grid application performance optimization –End to end performance analysis –Test and provide enhanced network and transport services : Premium, Scavenger, Multicast

39. 39 WP7 and other collaborations WP7 and EU DataTAG collaboration –QoS service study and experiment –High Throughput study and experiment –Network monitoring and measurement GGF –GHPN research group Other European Grid projects (FR e-toile, UK e-science, INFN grid…)

40. 40 For more information Consult our sites: –http://ccwp7.in2p3.frhttp://ccwp7.in2p3.fr –http://eu-datagrid.web.cern.ch