Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs Real-Time Visualization of IP Streams Over Switched WANs Timothy J. Salo Network Computing Services, Inc.

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 2 Contents Our objectives Our real-time visualization tool Our offer Our research (time permitting)

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 3 Overview DARPA-funded research project to explore the behavior of IP protocols in switched environments (particularly in WANs) We believe that the mapping of IP streams onto a collection of switched connections is an important, general problem We have developed a real-time visualization tool We are looking for places to deploy the tool

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 4 Overview We observed apparent anomalies in MAGIC wide-area IP/ATM testbed Anomalies appeared related to the protocols that map IP streams onto underlying switched connections (ATM SVCs) We wanted a real-time, global, fine-grained view of the behavior of IP and the underlying switched connections

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 5 Origins We wanted a real-time view of the network Demo

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 6 The Visualization Tool Displays graphically, in real-time, IP-related streams in wide-area IP/ATM internets Focuses on mapping of IP streams onto switched connections Allows researchers to interactively control the visualization Allows researchers to store and replay data Initially, supports IP/ATM

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 7 The Visualization Tool Completely written in Java –Compiles under Java 1.1 –Works better under Java 1.2 –Will be released with Berkeley-style copyright Object-oriented design –UML description of class hierarchy JavaDoc documentation

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 8 The Visualization Tool

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 9 The Visualization Tool Composed of two components –Data collection and analysis subsystem –Visualization subsystem

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 10 The Visualization Tool Data collection and analysis subsystem –Extracts data from the network using SNMP –“Auto-discovers” network topology –Creates a model of the network topology/state –Updates the model as the network state changes –Sends “model updates” to the visualization subsystem serialized Java objects complete model can be created from updates model updates can be written to file

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 11 The Visualization Tool Visualization subsystem –Runs as an applet or an application –Receives model updates from the data collection and analysis subsystem (or a file) –Maintains a model of the network topology/state –Displays the state of the network under operator control

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 12 The Visualization Tool Visualization system running on small networks Less information in MIBs than expected –Standard MIBs not always implemented –MIB often designed to expose variables, not support operations or research We want to deploy this on larger networks

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 13 Visualization Demo University LAN Demo Internal LAN Demo Local Demo

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 14 Our Offer We are looking for moderate-sized networks on which to deploy our tool! –Wide-area networks or campus networks –IP over ATM –Perhaps, MPLS We will: –Install and operate the tool –Put a person on site, if necessary –Add support for your switch vendor’s MIBs –Extend the software, time permitting

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 15 More Information Credit This work is sponsored by the Defense Advanced Research Projects Agency (DARPA) under contract number F C-0211.

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 16 Terminology stream an aggregate of one or more flows, treated as one flow for the purpose of forwarding in L2 and/or L3 nodes

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 17 Our Research We believe that making IP protocols work gracefully over switched connections is a general problem Switched connections are ubiquitous –IP/ATM (Classical IP, LANE, NHRP MPOA) –MPLS –Tunnels (Mobile IP) –Reservations (RSVP) –Wavelengths

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 18 Our Research Many IP protocols don’t work well with switched connections –Routing protocols (rapid topology changes) Compare process of installing a new leased line with establishing a switched connection –Adding a leased line involves lots of manual processes and time (~100 days) –Adding a switched connection (in some sense) compresses all of this work into 100 msec

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 19 Our Research Where can things go wrong in IP over switched services WANs? –Maintaining a collection of connections Stability Why is there a connection between these nodes? Why not one here? Response to resource depletion –Assigning flows to connections Why do packets take that path? –Behavior of IP/switched-services “control” traffic versus data

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 20 Our Research Our model of IP-over-switched-services protocols includes four functions: –Maintain a collection of connections Connections may be provided by an underlying link-layer network Connections maintained by IP software –Maintain routing tables for switched connections –Classify packets into streams –Assign streams to switched connections We believe this model has general applicability

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 21 Our Research Problems can be introduced at: –Network configuration time –Protocol design time

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 22 Religious Issues ATM, virtual circuits, traffic engineering, … easily generate a lot of discussion I believe that interactions between switched connections and the IP protocols include most of the interesting issues in this area I believe that many IP protocols don’t work well with switched connections –Routing protocols (rapid topology changes) –Traffic engineering (automated network design)

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 23 Religious Issues I believe that switched connections are pervasive in IP networks –Switched link-layer services –Within IP protocols Mobile IP, MPLS, VPNs, … ATM is not the issue –Use ATM when it is cost effective [and works] – nothing more needs to be said –The cost characteristics of ATM have clearly altered the technical and political evolution of the Internet

Network Computing Services, Inc. Real-Time Visualization of IP Streams over Switched WANs 6/13/00 Copyright ©2000 Network Computing Services, Inc. 24 Religious Issues “Virtual circuits” are not the issue –I don’t think I can really define a virtual circuit anymore… –Should we avoid frame relay because it uses “virtual circuits”? –Unknown or variable bandwidth might be an issue, but it’s not a major issue