2. DSGraph Distributed Snapshot Graph Algorithms & visualization

3. June 03Created by Ophir Ovadia2 Participants Student: Ovadia Ophir Lab instructor: Mr. Melamed Roie Lab chief engineer: Dr. David Ilana Tehcnion - faculty of Electrical Engineering – Software Lab

4. June 03Created by Ophir Ovadia3 Abstract DSGraph was developed to extract information about graphs’ properties and structure. These graphs represent a snapshot of a distributed system of connections.

5. June 03Created by Ophir Ovadia4 Information retrieval Information retrieval is accomplished in Two strategies: – Textually presented information. – Visually presented information.

6. June 03Created by Ophir Ovadia5 Information retrieval (cont) Textually presented information: – DSGraph gathers both overall and statistical information. – Information is gathered through execution of graph theory algorithms, variations on those algorithms and algorithms developed especially for DSGraph. – These include algorithms such as: BFS Number of connected components Number of disjoint paths between vertices More...

7. June 03Created by Ophir Ovadia6 Information retrieval (cont) Visually presented information: – DSGraph outputs visual graphs’ layouts meant to be viewed with two tools: GraphViz – relatively small (or reduced) graphs, highly customizable, has clusters, colors etc. Embedder – huge graphs, very fast but harder to understand.

8. June 03Created by Ophir Ovadia7 Information retrieval (cont) Visual information (cont): – Exhibiting large and heavily connected graphs is very difficult, therefore several methods are used for this task: Display the graph as is (for completeness). Display the BFS search tree (actually performs the connected components algorithm since the whole graph has to be covered). Display a reduction of the graph (the scale is customizable) while keeping its overall structure intact (see the report).

9. June 03Created by Ophir Ovadia8 Sample layout – 100 vertices

10. June 03Created by Ophir Ovadia9 Same graph another layout

11. June 03Created by Ophir Ovadia10 Software Design DSGraph was designed with great care to follow the Object Oriented Programming & Design scheme. DSGraph ’s design promotes its extendibility and reusability in a very easy and strait forward manner. DSGraph is written in C++. Code is extensively documented and follows strict coding guidelines. Design patterns are heavily employed.

12. June 03Created by Ophir Ovadia11 Software Design (cont) Design Patterns: – Singleton – the driver of the system. – Controller – the controller of the system. – Strategy – algorithms. – Visitor – variations on the algorithms.

13. June 03Created by Ophir Ovadia12 Class Diagram – visitors and algorithms interactions.

14. June 03Created by Ophir Ovadia13 The End Author: Ophir Ovadia Software Lab Faculty of Elecrical Engineering Technion The End