18/09/2002Presentation to Spirent1 Presentation to Spirent 18/09/2002

18/09/2002Presentation to Spirent2 Agenda Presentation: Scope and Reasons. Active “Grid Networking” Projects Tests & Measurements

18/09/2002Presentation to Spirent3 Scope What do we do? MISSION: “Demonstrate e2e managed bandwidth services in a multi- domain environment, in the context of Grid project requirements.” What does it involve ?  Managed bandwidth and Quality-of-Service provision  High performance, high bandwidth data transfers  Demonstrate end-to-end network services  Network Resources Reservation  An end-to-end Technology Trial (MPLS, DiffServ, Inter-domains, …)

18/09/2002Presentation to Spirent4 Why ? (case for Physics Particles)

18/09/2002Presentation to Spirent5 Why ? (distributed data in the Grid framework) Online System ~ MBytes/sec ~PByte/sec CERN 700k SI95 ~1 PB Disk; Tape Robot Tier 0 +1 Tier 1 ~2.5 Gbps FNAL: 200k SI95; 600 TB IN2P3 Center INFN Center RAL Center Tier2 Center 2.5 Gbps Tier2 Center Tier 2 Institute ~0.25TIPS Workstations 0.1–1 Gbps Physics data cache ~2.5 Gbps Tier 3 Tier 4 Giga- (G) 10 9 Tera- (T) = 1000G Peta- (P) = G

18/09/2002Presentation to Spirent6 Grid Project DataGRID Sites In Europe

18/09/2002Presentation to Spirent7 Grid Sites in UK Cambridge Newcastle Edinburgh Oxford Glasgow Manchester Cardiff Southampton London Belfast DL RAL Hinxton “Production Network” managed by UKERNA (1Gb – 10Gb)

18/09/2002Presentation to Spirent8 Active “Grid Networking” Projects MB-NG (  Currently it is the main project in the network research community in UK.  High Throughput, e2e QoS in UK over “Development Network” (managed by UKERNA).  Funded by UK research councils (PPARC, EPSRC,…). DataTAG (  Large-scale intercontinental testbed for data-intensive Grids  High Throughput, e2e QoS between Geneva and Chicago  Funded by the European Commission – EU Grant IST

18/09/2002Presentation to Spirent9 “Development Network” Gigabit Ethernet 2.5 Gbit POS Access 2.5 Gbit POS core MPLS Admin. Domains Dark Fiber (SSE) POS WorldCom Leeds SJ4 Dev C-PoP Warrington SJ4 Dev C-PoP London UCL OSM- 4GE- WAN- GBIC UCL OSM- 4GE- WAN- GBIC MCC OSM- 4GE- WAN- GBIC MAN OSM- 4GE- WAN- GBIC RAL OSM-4GE- WAN-GBIC RAL OSM- 4GE- WAN- GBIC OC48 SJ4 Dev ULCC OC48 WorldCom SJ4 Dev C-PoP Reading OC48 ULCC OC48 MB - NG UKERNA Also for other projects like IPv6.

18/09/2002Presentation to Spirent10 MB-NG Partners Partners: SPIRENT, CISCO, ACTERNA, UKERNA, CLRC-RAL, CLRC-DARESBURY, Manchester, UCL + plus Lancaster and Southampton + Jon Crowcroft (Cambridge)

18/09/2002Presentation to Spirent11 DataTAG Project EU Transatlantic Grid project EU Partners:CERN/PPARC/INFN/UvA/INRIA US Partners: Caltech, ESnet, Abilene, PPDG, iVDGL… The main focus are: –Grid Network Research including: Provisioning (CERN) Investigations of high performance data transport (PPARC) End-to-end inter-domain QoS + BW Network resource reservation Bulk data transfer and monitoring (UvA) –Interoperability between Grids in Europe and the US PPDG, GriPhyN, DTF, iVDGL (USA)PPDG, GriPhyN, DTF, iVDGL (USA)

18/09/2002Presentation to Spirent12 DataTAG Layout Abilen e ESNE T UK SuperJANET4 IT GARR -B IT GARR -B GEANT NL SURFnet NL SURFnet 2.5 Gbit PoS lambda SLAC Cisco Juniper Alcatel Cisco Juniper Alcatel Giga Switch Juniper Light Switch Giga Switch Cisco 6509 Juniper Light Switch CERN (Geneva) Starlight (Chicago) Fermi

18/09/2002Presentation to Spirent13 Spirent How Spirent can help us?  Generation of “realistic internet” Traffic.  Traffic needs to be “DiffServ” marked. (Three Classes: EF, LBE, BE).  Gigabit / OC48 POS interfaces capability.  Reliable and Highly accurate timing measurements.  Capable of generating traffic on schedule.

18/09/2002Presentation to Spirent14 Measurements Generic Metrics.  One Way Delay / Latency  Throughput  Jitter  Packet Loss  Consecutive Packet Loss

18/09/2002Presentation to Spirent15 Traffic Scenarios Traffic Distributions.  “Constant Bit Rate” (CBR)  “Exponential Distributions” (EXP)  “Heavy Tail Distributions” (HT) QoS Traffic.  DiffServ Enabled.  Classes  Strict Priority (EF)  AF ?  Less Best Effort (LBE)  Best Effort (BE)

18/09/2002Presentation to Spirent16 Specific Tests Latency vs. Packet Size Throughput vs. Packet Size  For both: UDP and TCP.  For all Traffic Scenarios: CBR, EXP and HT.  For each Class: EF, LBE, BE

18/09/2002Presentation to Spirent17 Accuracy Critical for “One Way Delay” & Jitter Bounding the error in measurement. GPS needed (Src/Dst), specially for long trunks:  London – Manchester (MB-NG)  Geneva – Chicago (DataTAG) Man Lon Worst Case Scenario: 72 Bytes Frame

18/09/2002Presentation to Spirent18 Flows Dependency For TCP only, “Checking dependency on the number of Flows”. Repeating the Tests:  Latency vs. Packet Size  Throughput vs. Packet Size

18/09/2002Presentation to Spirent19 “Bursty” Traffic Packet Loss vs Burst Size.  CBR Traffic Scenario.  Measuring “Packet Loss” changing the duration of the “Burst Window” for a given traffic rate.  Repeating changing the traffic rate. 100ms200ms…10s 1Mbps 0.01%0.2%1% 2Mbps %% … %% 100Mbps %% CBR Burst Window (T) OFFON T

18/09/2002Presentation to Spirent20 I/O Rates Sent Rate vs. Received Rate.  Interesting in the “Device Calibration Stage” in the lab.  Wire Rate level (with constant packet size).  UDP/TCP  Repeat changing packet sizes. Sent Rate Received Rate

18/09/2002Presentation to Spirent21 Long Transfer Tests Latency vs. File Size.  Controlling the File Size.  Can we do that?.  UDP/TCP

18/09/2002Presentation to Spirent22 TCP Packet Re-sequencing Detection.  How can it be measured ?  Determination of Cause (why ?)  Determination of Location (where ?) Effectiveness of Congestion Control Strategies.  Drop strategies (eg, RED, TailDrop,.. ).  Policing (eg. In case of congestion decrease class priority).  ECN (eg. Interaction with RED and “rogue” end systems)

18/09/2002Presentation to Spirent23 Open Questions Spirent TCP stack implementation.  Any ACK in the TCP ?. Generation of Realistic Traffic.  Packet Sizes / Distributions / Number of Flows Spirent devices to simulate Transatlantic Delays Measuring Consecutive Packet Loss Playback Recorded Traffic Load specified per class/flow, not shared load per port Measuring effects of Traffic policing (reclassification) FEC-UDP implementation (Forwarding Error Correction)

18/09/2002Presentation to Spirent24 Thank You…