18/09/2002Presentation to Spirent1 Presentation to Spirent 18/09/2002.
-
Upload
austin-ball -
Category
Documents
-
view
224 -
download
0
description
Transcript of 18/09/2002Presentation to Spirent1 Presentation to Spirent 18/09/2002.
18/09/2002 Presentation to Spirent 1
Presentation to Spirent18/09/2002
18/09/2002 Presentation to Spirent 2
Agenda
Presentation: Scope and Reasons.
Active “Grid Networking” Projects
Tests & Measurements
18/09/2002 Presentation to Spirent 3
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, …)
18/09/2002 Presentation to Spirent 4
Why ? (case for Physics Particles)
18/09/2002 Presentation to Spirent 5
Why ? (distributed data in the Grid framework)
Online System
~100-400 MBytes/sec
~PByte/sec
CERN 700k SI95 ~1 PB Disk; Tape RobotTier 0 +1
Tier 1 ~2.5 GbpsFNAL: 200k SI95; 600 TBIN2P3 Center INFN Center RAL Center
Tier2 Center2.5 Gbps
Tier2 CenterTier2 CenterTier2 CenterTier2 Center Tier 2
Institute ~0.25TIPS
Workstations0.1–1 GbpsPhysics data
cache
~2.5 GbpsTier 3
Tier 4
Giga- (G) 109
Tera- (T) 1012 = 1000GPeta- (P) 1015 = 1000000G
18/09/2002 Presentation to Spirent 6
Grid Project
DataGRID
SitesIn
Europe
18/09/2002 Presentation to Spirent 7
Grid Sites in UK
Cambridge
Newcastle
Edinburgh
Oxford
Glasgow
Manchester
Cardiff
SouthamptonLondon
Belfast
DL
RAL Hinxton
“Production Network”
managed by UKERNA
(1Gb – 10Gb)
18/09/2002 Presentation to Spirent 8
Active “Grid Networking” Projects
MB-NG (http://www.mb-ng.net)
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 (http://datatag.web.cern.ch)
Large-scale intercontinental testbed for data-intensive Grids
High Throughput, e2e QoS between Geneva and Chicago
Funded by the European Commission – EU Grant IST-2001-32459 .
18/09/2002 Presentation to Spirent 9
“Development Network”
Gigabit Ethernet2.5 Gbit POS Access2.5 Gbit POS coreMPLS Admin. Domains
Dark Fiber (SSE)POS
WorldCom
LeedsSJ4 DevC-PoP
Warrington12416
SJ4 DevC-PoP
London12416
UCLOSM-4GE-WAN-GBIC
UCLOSM-4GE-WAN-GBIC
MCCOSM-4GE-WAN-GBIC
MANOSM-4GE-WAN-GBIC
RALOSM-4GE-WAN-GBICRAL
OSM-4GE-WAN-GBIC
OC48
SJ4 DevULCC12016
OC48
WorldComSJ4 DevC-PoP
Reading12416
OC48ULCC
OC48OC48
OC48
MB - NG
UKERNA Also for other projects like IPv6.
18/09/2002 Presentation to Spirent 10
MB-NG Partners
Partners:SPIRENT,CISCO,ACTERNA,UKERNA,CLRC-RAL, CLRC-DARESBURY, Manchester, UCL+ plus Lancaster and Southampton+ Jon Crowcroft (Cambridge)
18/09/2002 Presentation to Spirent 11
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)
18/09/2002 Presentation to Spirent 12
DataTAG Layout
Abilene
ESNET
UKSuperJANET4
ITGARR-B
GEANT
NLSURFnet
2.5 Gbit PoS lambda
SLAC
Cisco
Juniper
Alcatel
Cisco
Juniper
AlcatelGigaSwitch
JuniperLight
SwitchGigaSwitch
Cisco6509
JuniperLight
Switch
CERN (Geneva)Starlight (Chicago)
Fermi
18/09/2002 Presentation to Spirent 13
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.
18/09/2002 Presentation to Spirent 14
Measurements
Generic Metrics. One Way Delay / Latency
Throughput
Jitter
Packet Loss
Consecutive Packet Loss
18/09/2002 Presentation to Spirent 15
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)
18/09/2002 Presentation to Spirent 16
Specific TestsLatency 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
18/09/2002 Presentation to Spirent 17
AccuracyCritical 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
sGbpsBytes 23.05.2
8*72
Worst Case Scenario: 72 Bytes Frame
18/09/2002 Presentation to Spirent 18
Flows Dependency
For TCP only, “Checking dependency on the number of Flows”.
Repeating the Tests: Latency vs. Packet Size
Throughput vs. Packet Size
18/09/2002 Presentation to Spirent 19
“Bursty” TrafficPacket 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.
100ms 200ms
… 10s
1Mbps 0.01% 0.2% 1%2Mbps % % %… % % %100Mbps
% % %
CBR
Burst Window (T) OFF ON
T
18/09/2002 Presentation to Spirent 20
I/O RatesSent 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
18/09/2002 Presentation to Spirent 21
Long Transfer Tests
Latency vs. File Size. Controlling the File Size.
Can we do that?.
UDP/TCP
18/09/2002 Presentation to Spirent 22
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)
18/09/2002 Presentation to Spirent 23
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)
18/09/2002 Presentation to Spirent 24
Thank You…