1. Distributed systems Module 2 -Distributed algorithms Teaching unit 1 – basic techniques Ernesto Damiani University of Bozen Lesson 1 – Introduction

2. Distributed Algorithms What is a distributed algorithm? Is it practical? Examples: Napster, Gnutella, etc.

3. Model basics (1) Anonymous

4. Model basics (2) With IDs 12 7 5 4 88 2

5. Model basics (3) Overlay network (mono or bi-directional) 12 7 5 4 88 2

6. Model basics (4) Ring 12 7 5 4 88 2

7. Model basics (5) Shared memory 12 7 5 4 88 2

8. Synchronous vs asynchronous communication model t t+d d: clock period t t+??

9. Algorithms overview Leader election Shortest path Consensus Secure sum Building blocks –Atomic memory, mutual exclusion, logical clocks FINE