Topics of Discussion

Transcription

1 TBI: End-to to-end Network Performance Testbed for Empirical Bottleneck Detection Prasad Calyam, OARnet,, A Division of The Ohio Supercomputer Center, The Ohio State University TRIDENTCOM, Trento,, Italy, February 2005 Dima Krymskiy, Mukundan Sridharan,, Paul Schopis 1

2 Topics of Discussion Third Frontier Network Measurement Project Basics of Network Measurement Infrastructures (NMIs) ActiveMon NMI Software TFN Beacon Infrastructure (TBI) Testbed End-to-End Network Performance Bottleneck Detection Case Studies! Work in progress Conclusion 2

3 Third Frontier Network The Third Frontier Network (TFN) funded by the Ohio Board of Regents A dedicated high-speed fiber-optic network linking Ohio colleges and universities with research facilities to promote research and economic development Over 1,600 miles of fiber has been purchased to create a network backbone in Ohio to connect colleges and universities, K-12 schools, and communities together 3

4 Third Frontier Network (2) 4

5 TFN Measurement Project Started in early 2004 Project funding from the Ohio Board of Regents To ensure that University campuses can effectively use the advanced networking services the new network provides Project Partners OARnet (Project Lead and Co-ordination) University of Cincinnati, Cincinnati State, The Ohio State University, Kent State University, Southern State Community College, University of Toledo, Wright State University 5

6 Project Goals Identify end-to-end performance bottlenecks in the TFN on an ongoing fashion by building a comprehensive Network Measurement Infrastructure (NMI) Test new and advanced technologies and equipment before wide-scale adoption in the TFN Higher Education communities Technologies: H.323/SIP based Voice and Videoconferencing, MPEG3, HDTV, Multicast, Bulk FTP Equipment: Video streaming Caches, Firewalls, Intrusion Detection Systems, Traffic shapers Bring awareness and train campus-networking professionals to make optimum use of the capabilities of TFN so that their campus network infrastructures can be upgraded suitably 6

7 Project Goals Identify end-to-end performance bottlenecks in the TFN on an ongoing fashion by building a comprehensive Network Measurement Infrastructure (NMI) Test new and advanced technologies and equipment before wide-scale adoption in the TFN Higher Education communities Technologies: H.323/SIP based Voice and Videoconferencing, MPEG3, HDTV, Multicast, Bulk FTP Equipment: Video streaming Caches, Firewalls, Intrusion Detection Systems, Traffic shapers Bring awareness and train campus-networking professionals to make optimum use of the capabilities of TFN so that their campus network infrastructures can be upgraded suitably 7

8 What constitutes the infrastructure in an NMI? Measurement Toolkit hosted on Beacon servers Scheduler for measurement orchestration between multiple measurement servers Large database for storage and archiving measurement data Analysis Engine and web service for visualization of network performance data AAA procedures for handling Security/Privacy Issues 8

9 A Typical NMI 9

10 Examples of NMI Software and Deployments NIMI (Developed by Vern Paxson, currently maintained by NLANR) Surveyor (Developed by Advanced, currently maintained by Univ. Of Wisconsin) AMP (NLANR) IEPM-BW (SLAC) Scriptroute (Univ. of Washington) E2E pipes (Internet2) Many Many More (ETOMIC, D-ITG, ) ActiveMon (Being developed by OARnet) 10

11 ActiveMon NMI Software An application-specific active measurement toolkit To identify bottlenecks pertaining to specific applications; e.g., Voice and Video over IP (Delay, Jitter, Loss, Reordering), Bulk FTP flows (Throughput, Available/Bottleneck Bandwidth, Web server/ Oracle server response times, etc An advanced active measurements scheduler- OnTimeMeasure To orchestrate and regulate network-wide active measurements An analysis engine with web interface To correlate performance along multiple paths To generates appropriate alerts for concerned personnel! Support for federated measurements To support end-to-end performance debugging along multiple ISP domains 11

12 ActiveMon Measurement Toolkit Tools used for end-to-end network performance data collection Ping (Delay) Open Source Traceroute (Topology) Open Source Iperf (TCP/UDP Bandwidth Performance) Open Source Pathchar (Hop-by-Hop performance) Open Source Pathload (Available Bandwidth) Open Source Pathrate (Bottleneck Bandwidth) Open Source OWAMP (µs Precision Delay CDMA+NTP) Open Source H.323 Beacon (Voice/Video Performance) Open Source apparenet (Hop-by-Hop Performance) Commercial NetQoS (Application Response Times) Commercial 12

13 OnTimeMeasure Scheduler Active measurements can encroach network bandwidth required for actual application traffic Active measurements need to be regulated Running multiple simultaneous measurements on monitoring probes could result in misleading reports of network performance Active measurements require dedicated system and network resources Network Interface Card (NIC), CPU processing, Application ports, Multimedia codecs, Bandwidth, Active measurements between measurement beacons need to be orchestrated 13

14 Results in a LAN with WAN Emulation! 14

15 OnTimeMeasure Framework 15

16 OnTimeMeasure Framework 16

17 ActiveMon Analysis Engine To retrieve relevant summary-views of the large network-wide active measurement datasets Weather-map functionality, Query-able XML schemas, To effectively identify anomalies and alert relevant support and operations personnel Target for a low probability of false-alarms Cover anomalies that indicate better/poor/marginal changes To perform multi-path data correlation to isolate performance problems involving multiple-links Observed end-to-end performance is a function of performance of individual intermediate links 17

18 Example: Alarm check to notify network health status Watermarks for Good, Acceptable and Poor grade of audiovisual quality as experienced by end-user Delay: (0-150)ms, ( )ms, > 300ms Jitter: (0-20)ms, (20-50)ms, > 50ms Loss: (0-0.5)%, ( )%, >1.5% Prasad Calyam, Mukundan Sridharan, Weiping Mandrawa, Paul Schopis, Performance Measurement and Analysis of H.323 Traffic, Proceedings of Passive and Active Measurement Workshop (PAM),

19 TFN Beacon Infrastructure (TBI) Testbed 19

20 TFN Beacon Infrastructure (TBI) Testbed 20

21 Paths being Measured 21

22 Purpose of TBI Testbed To understand network end-to-end performance characteristics Via partial path and intermediate bottleneck hop analysis To understand network performance measurement data reported by various tools How good are they to empirically correlate network events in a routine monitoring infrastructure? To compare performance at campus, regional, national-academic and national-commerical backbone network levels To quantify end-to-end network performance stability in the Internet 22

23 End-to-End Network Performance Bottleneck Detection Case Studies! Anomalies in measured paths (2-month period) Effects of route changes Network device misconfiguration Misrepresentation of network health by measurement tool misconfiguration Performance comparison of campus, regional, national-academic and nationalcommercial backbone networks using H.323 Beacon 23

24 Effects of route changes RTT OSUB to OSUL Jitter OSUB to OSUL (both directions) RTT OSUL to OSUB 24

25 Effects of route changes (2) RTT OSUB to UOCB RTT UOCB to OSUB 25

26 Network device misconfiguration Available Bandwidth OSUB to UOCB 26

27 Ocean Wave Anomaly of OWAMP RTT UOCB to OSUB 27

28 H.323 Beacon* An application-specific measurement tool To monitor and qualify the performance of H.323 Videoconferencing sessions at the host and in the network (end-to-end) Useful to an end-user/conference operator/network engineer Addresses problems due to H.323 protocol-specific idiosyncrasies Can be generalized to RTP packets performance over the network Many in-built tools that generate various kinds of measurement data for pre/during/post Videoconference troubleshooting! An easy to install and use tool that is open source * Project supported by Internet2, The Ohio Board of Regents, OARnet 28

29 A few H.323 Beacon screenshots 29

30 Performance comparison of academic and commercial network backbones using H.323 Beacon Most Stable Least Stable Academic networks most suitable for Voice and Video over IP applications Bottlenecks of multi-domain/last-mile links mainly impact end-to-end performance 30

31 ActiveMon work in progress Extend testbed into a production-level NMI spanning TFN and major Ohio-based University Campuses Better multi-link data correlations in Analysis Engine DDoS anomaly detection using active measurement data signatures OnTimeMeasure extensions using real-time scheduling principles for various active measurement specifications Better visualization module Planning on ActiveMon 1.0 release on sourceforge (Summer 2005) 31

32 Thanks! Scripts Development and Data Analysis Mukundan Sridharan, Dima Krymskiy, Phani Kumar Arava Project Management Steve Gordon, Paul Schopis OSU Border and Lab Deployment Prof. David Lee, Dave Kneisly, Arif Khan, Weiping Mandrawa UC Border and Lab Deployment Prof. Jerry Paul, Prof. Fred Annexstein, Bruce Burton, Bill Bohmer, Tom Ridgeway, Michal Kouril, Diana Noelcke NCSU Deployment John Moore, Chintan Desai Tools Deployment Loki Jorgenson, Chris Norris (apparenet) Jeff Boote (OWAMP) Leandro Lustoza (H.323 Beacon E-Model implementation) 32

33 Questions? TFN Measurement Project Reference: 33