1. GridPP meeting Feb 03 R. Hughes-Jones Manchester WP7 Networking Richard Hughes-Jones

2. GridPP meeting Feb 03 R. Hughes-Jones Manchester WP7: Networking for Grids u Grid Network monitoring n Provide information for Middleware & Applications – Network Cost Function n Understand the networks we use n Provide Information for capacity planning u Creation of schemas and publishing the monitoring data u Investigation of Protocols TCP and non-TCP n Testing the work of CS groups / IETF NOT inventing u Close technical collaboration with NRNs, DANTE and the DataTAG project u The High Bandwidth High Throughput Challenge n Investigation of end Host Networking and Disk sub-systems n To show what can be achieved on production networks with: l Multiple streams of TCP packets l Tuned TCP parameters l Different TCP stacks u Applying the knowledge to the real Grid user community

3. GridPP meeting Feb 03 R. Hughes-Jones Manchester Network Monitoring – Technology  e-Sci

4. GridPP meeting Feb 03 R. Hughes-Jones Manchester NetworkCost Architecture PCP Distributed Data Collector Raw IPerfUDPmonGridFTPPingEr Measure Collect And Storage Processing Archive NetworkCost R-GMA Globus MDS

5. GridPP meeting Feb 03 R. Hughes-Jones Manchester NetworkCost functionality 13,084,046,534,5 CNAF 7,086,2410,385,03 IN2P3 2,6611,863,2511,13 NIKHEF 4,357,122,447,46 RAL 35,4444,8777,7846,75 CERN CNAFIN2P3NIKHEFRALCERN cost[][] = getNetworkCost (SE[], SE[]) FileSize= 11 MB

6. GridPP meeting Feb 03 R. Hughes-Jones Manchester High throughput transfer challenges u Large amounts of data have to be transferred between Mass Storage Systems and CEs in Europe (and world wide!) u EU demonstration sent HEP data from CERN to NIKHEF/SARA at high rates n It was to show what can be achieved with: l Multiple streams of TCP packets l Tuned TCP parameters: ­ Interface txqueuelen 2000 ­ TCP buffer size to match the BW * rtt l Different TCP stacks: ­ Standard TCP ­ Fast TCP ­ Scalable TCP l Fair sharing between stacks u This highlights the results of close technical collaboration with NRNs, DANTE and other projects: DataTAG, Mb-NG, UK- Star- Nether- Light

7. GridPP meeting Feb 03 R. Hughes-Jones Manchester Demo Setup for the EDG Review SurfNet NIKHEF CERN GEAN T u Shows data transfers from Mass Storage system at CERN to Mass Storage system at NIKHEF/SARA u Disk sub-system I/O bandwidth of ~70 MB/s u All systems have Gigabit Ethernet connectivity u Use GridFTP and Measure disk to disk performance

8. GridPP meeting Feb 03 R. Hughes-Jones Manchester Demo Consisted of: Raid0 Disk Data over TCP Streams Raid0 Disk GridFTP Dante Monitoring Node Monitoring Site Monitoring

9. GridPP meeting Feb 03 R. Hughes-Jones Manchester SuperJANET4 CERN Sara & NIKHEF SURFnet European Topology: NRNs, Geant, Sites

10. GridPP meeting Feb 03 R. Hughes-Jones Manchester Throughput on the day ! The view from GÉANT – with thanks to Dante

11. GridPP meeting Feb 03 R. Hughes-Jones Manchester Some Measurements of Throughput CERN -SARA u Using the GÉANT Backup Link n 1 GByte file transfers u Standard TCP n Average Throughput 167 Mbit/s n Users see 5 - 50 Mbit/s! u High-Speed TCP n Average Throughput 345 Mbit/s u Scalable TCP n Average Throughput 340 Mbit/s

12. GridPP meeting Feb 03 R. Hughes-Jones Manchester What the Users Really find: u CERN – RAL using production GÉANT n CMS Tests 8 streams n 50 Mbit/s @ 15 MB buffer n Firewall 100 Mbit/s u NNW – SJ4 Access n 1 Gbit link

13. GridPP meeting Feb 03 R. Hughes-Jones Manchester WP7 High Throughput Achievements u Close Collaboration with Dante u “Low” layer QOS testing over GEANT n LBE n IP premium u iGrid 2002 and ER 2002 : UDP with LBE n Network performances evaluation u EU Review 2003 : application level transfer with real data between EDG sites n proof of concept

14. GridPP meeting Feb 03 R. Hughes-Jones Manchester Conclusions u More research on TCP stacks and its implementation is needed n ie HEP-style applied research - u Continue the collaboration with NRNs & Dante to: n Understand the behavior of National networks & GEANT backbone n Learn the benefits of QoS deployment u WP7 is taking the “Computer Science” research and knowledge of the TCP protocol & implementation and applying it to the network for real Grid users u Enabling Knowledge Transfer to sysadmins and end users n EDG release 1.4.x has configuration scripts for TCP parameters for SE and CE n Network tutorials for end users n Work with users – focus on 1 or 2 sites to try to get improvements