CS4231
Parallel and Distributed Algorithms
AY 2006/2007 Semester 2
Lecture 8
Instructor: Haifeng YU
Review of Last Lecture
Chapter 13 Leader Election
Leader election on a ring
Chang-Roberts Algorithm
Interesting avg performance analysis
Leader electi

Algorithms for COOPERATIVE DS:
Leader Election in the MPS
model
1
Leader Election (LE) problem
In a DS, it is often needed to designate a
single processor (i.e., a leader) as the
coordinator of some forthcoming task (e.g.,
find a spanning tree using the

Minimum Spanning
Trees
GHS algorithm
Based on A distributed
algorithm for minimum-weight
spanning trees,
Gallager, Humblet, Spira 1983
, -
2004 ,
Model
Asynchronous network
Network is represented by an undirected
connected weighted graph
N processors re

Maximal Independent Set
1
Independent Set (IS):
Any set of nodes that are not adjacent
2
Maximal Independent Set (MIS):
An independent set that is no
subset of any other independent set
3
A Sequential Greedy algorithm
I
I
Suppose that
Initially
will hold

6.852: Distributed Algorithms
Leader election in a synchronous ring
Algorithms in general synchronous networks
lower bound for comparison-based algorithms
non-comparison-based algorithms
leader election
breadth-first search
broadcast and convergecast
shor

6.852: Distributed Algorithms
Spring, 2008
Instructors: Nancy Lynch, Victor Luchangco
Teaching Assistant: Calvin Newport
Course Secretary: Joanne Hanley
Distributed algorithms
Algorithms that are supposed to work in distributed
networks, or on multiproce

Leader Election in rings
All nodes are equal, but some are more equal than others
Marco Aiello, Eirini Kaldeli
University of Groningen
Distributed Systems, 2009
Marco Aiello, Eirini Kaldeli (RuG)
Leader Election in rings
Distributed Systems, 2009
1 / 26
O

6.852: Distributed Algorithms
Spring, 2008
Class 4
Todays plan
Fault-tolerant consensus in synchronous systems
Link failures:
The Two Generals problem
Process failures:
Stopping and Byzantine failure models
Algorithms for agreement with stopping and

6.852 Lecture 3
Algorithms in general synchronous networks
(continued)
breadth-first search
broadcast, convergecast
shortest paths
minimum-weight spanning tree
Last lecture
Lower bound for comparison-based leader
election in a ring
Leader election in gene