d02d5d77f798c50c825962b59f0e57d6.ppt
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TBI: End-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
Topics of Discussion Third Frontier Network Measurement Project Basics of Network Measurement Infrastructures (NMIs) “Active. Mon” NMI Software TFN Beacon Infrastructure (TBI) Testbed End-to-End Network Performance Bottleneck Detection Case Studies! Work in progress… Conclusion 2
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
Third Frontier Network (2) 4
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
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, MPEG 3, 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
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, MPEG 3, 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
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
A Typical NMI 9
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) E 2 E pi. PES (Internet 2) Many More… (ETOMIC, D-ITG, …) Active. Mon (Being developed by OARnet) 10
“Active. Mon” 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”On. Time. Measure” 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
Active. Mon 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 appare. Net (Hop-by-Hop Performance) Commercial Net. Qo. S (Application Response Times) Commercial 12
“On. Time. Measure” 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
Results in a LAN with WAN Emulation! 14
On. Time. Measure Framework 15
On. Time. Measure Framework 16
Active. Mon 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
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, (150 -300)ms, > 300 ms Jitter: (0 -20)ms, (20 -50)ms, > 50 ms Loss: (0 -0. 5)%, (0. 5 -1. 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), 2004 18
TFN Beacon Infrastructure (TBI) Testbed 19
TFN Beacon Infrastructure (TBI) Testbed 20
Paths being Measured 21
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
End-to-End Network Performance Bottleneck Detection Case Studies! Anomalies in measured paths… month period) (2 - Effects of route changes Network device misconfiguration Misrepresentation of network health by measurement tool misconfiguration Performance comparison of campus, regional, national-academic and national-commercial backbone networks using H. 323 Beacon 23
Effects of route changes RTT OSUB to OSUL Jitter OSUB to OSUL (both directions) RTT OSUL to OSUB 24
Effects of route changes (2) RTT OSUB to UOCB RTT UOCB to OSUB 25
Network device misconfiguration Available Bandwidth OSUB to UOCB 26
“Ocean Wave” Anomaly of OWAMP RTT UOCB to OSUB 27
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 Internet 2, The Ohio Board of Regents, OARnet 28
A few H. 323 Beacon screenshots… http: //www. itecohio. org/beacon 29
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
Active. Mon 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 DDo. S anomaly detection using active measurement data signatures On. Time. Measure extensions using real-time scheduling principles for various active measurement specifications Better visualization module… Planning on Active. Mon 1. 0 release on sourceforge (Summer 2005) http: //sourceforge. net/projects/activemon/ 31
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 (appare. Net) Jeff Boote (OWAMP) Leandro Lustoza (H. 323 Beacon E-Model implementation) 32
Questions? TFN Measurement Project Reference: http: //tfn. oar. net/measurement 33
d02d5d77f798c50c825962b59f0e57d6.ppt