1. Computer Science 1 An Approach to Universal Topology Generation Alberto Medina Anukool Lakhina Ibrahim Matta John Byers http://www.cs.bu.edu/brite

2. Computer Science 2 Why Topology Generation?  To effectively engineer the Internet  Open Question: Are topologies generated by existing models representative of the Internet?  Our contribution is a universal topology generation framework

3. Computer Science 3 Main Features of BRITE  Flexible: supports multiple generation models  Extensible: allows adding new generation models  Interoperable: allows use of topologies from other topology generators  Portable: implemented in Java and C++  User Friendly: provides a GUI and configuration files.

4. Computer Science 4 The Big Picture Configuration File (Parameters) BRITE GT-ITM NLANR Skitter + BRITE GENERATION Engine BRITE ANALYSIS Engine BRITE NS SSF Min-Hop Paths Degree Rank Degree Freq Path Lengths output formats Imported file formats

5. Computer Science 5 BRITE Architecture Topology Graph Model Model 1 Nodes BRITE NS SSF Export Methods Model 2 Model n... Edges

6. Computer Science 6  A repository of analysis routines for topologies  Allows researchers to share analysis routines and create benchmarks to compare topologies  Fully integrated with BRITE but can also be used independently BRIANA: The BRITE Analysis Engine

7. Computer Science 7 Experimental Results NLANR Topology (04/98) BRITE Topology (Barabási-Albert Model) GT-ITM Topology (Flat)

8. Computer Science 8 Visualizing BRITE Topologies A BRITE generated topology (5K nodes, 10K edges) visualized in Otter

9. Computer Science 9  Large scale topological simulations are vital to verify abstractions and models of the Internet  SSFNet is a high performance (100K multi- protocol hosts and routers) simulation framework. A BRITE generated topology #BRITE topology output to SSFNET’s DML format Net [ frequency 1000000000 #1 nanosecond time resolution …. #ROUTERS ------------------------------------------------------- router [ id 0 graph [ProtocolSession [name ip use SSF.OS.IP] ProtocolSession [name ospf use SSF.OS.OSPF.sOSPF] ] interface [idrange [from 0 to 3] _extends.dictionary.100BaseT] ] …. #LINKS ------------------------------------------------------- link [ attach 0(1) attach 3760(1) delay 0.0 ] link [ attach 0(2) attach 1898(1) delay 0.0 ] … ] #end of NET Export to SSFNet BRITE Topologies in Large-Scale Simulations

10. Computer Science 10  Produce annotated topologies  Create Internet Simulation Environments  Develop models for dynamic topologies  Devise a taxonomy of metrics for topology analysis  Use BRITE and BRIANA to evaluate Internet protocols and algorithms Future Directions

11. Computer Science 11  A. Medina, A. Lakhina, I. Matta, and J. Byers. An Approach to Universal Topology Generation. Submitted to MASCOTS 2001. April, 2001.  A. Medina, I. Matta, and J. Byers. On the Origin of Power Laws in Internet Topologies. ACM Computer Communications Review, April 2000.  A. Medina, I. Matta, and J. Byers. BRITE 1.0: A Flexible Generator of Internet Topologies. BU-CS-TR- 2000-005. January 21, 2000.  A. Medina, A. Lakhina, I. Matta, and J. Byers. BRITE: Universal Topology Generation from a User's Perspective. BU-CS-TR-2001-003. April 05, 2001. Publications