CS 7880: Topics in Theoretical Computer Science

Network Algorithms

Tentative Calendar

Week
Topic and Reading
Handout
Jan 12
Administrivia
Review of probability and graph algorithms
Random walks in graphs
Cover time in regular graphs
Primary references:
Laszlo Lovasz, Random Walks on Graphs, 1994; Sections 0, 1, 2, and 3
Secondary references:
Michael Mitzenmacher and Eli Upfal, Probability and Computing, 2005, Chapter 7
Lecture Notes
Jan 15
Random walks in graphs
Cover time, mixing time, and spectral gap
Primary references:
Laszlo Lovasz, Random Walks on Graphs, 1994; Section 3 and first half of 5.
Lecture Notes
Jan 19
Random walks in graphs
Random walks and electrical networks
Rumor spreading and gossiping
Network diffusion processes
Analysis of push-based broadcast
Primary references:
Laszlo Lovasz, Random Walks on Graphs, 1994; Section 4
Feige, Peleg, Raghavan, and Upfal, Randomized broadcast in networks, RSA 2006
Secondary references:
Peter Doyle and J. Laurie Snell, Random walks and electrical networks, 1984, 2000, Chapter 1
Lecture Notes

Jan 22
Rumor spreading and gossiping
Analysis of the push-pull protocol in general graphs
Primary reference:
G. Giakkoupis,  Tight Bounds for Rumor Spreading for Graphs of a Given Conductance, STACS 2011
Secondary reference:
F. Chierichetti, S. Lattanzi, A. Panconesi, Rumor Spreading in Social Networks, ICALP 2009
F. Chierichetti, S. Lattanzi, A. Panconesi, Almost Tight Bounds for Rumor Spreading with Conductance, STOC 2010
G. Giakkoupis,  Tight Bounds for Rumor Spreading with Vertex Expansion, SODA 2014
Problem Set 1
Lecture Notes
Jan 26
Cris Moore Colloquium Talk: What can physics tell us about inference?

Jan 29
Rumor spreading and gossiping
Analysis of the push-pull protocol in general graphs
Primary reference:
G. Giakkoupis,  Tight Bounds for Rumor Spreading for Graphs of a Given Conductance, STACS 2011
Lecture Notes
Feb 2
Rumor spreading and gossiping
Optimal gossiping using network coding
Bernhard Haeupler, Analyzing Network Coding Gossip Made Easy, STOC 2010
Lecture Notes
Feb 5
Epidemics
The SIR model: Idealized analysis using branching processes
Rick Durrett, Random Graph Dynamics, Cambridge University Press
D. Easley and J. Kleinberg, Networks, Crowds, and Markets, Cambridge U. Press, 2010
Lecture Notes
Feb 9
Epidemics
The SIR model: Idealized analysis using branching processes
Talk on Reed-Solomon codes by Mary Wootters

Feb 12
Epidemics
Ganesh, Massoulie, and Towsley, The effect of network topology on the spread of epidemics, Infocom 2006
Upper bound on epidemic die-out in terms of spectral radius
Lecture Notes
Feb 16
Epidemics
Ganesh, Massoulie, and Towsley, The effect of network topology on the spread of epidemics, Infocom 2006
Lower bound on epidemic die-out time, when expansion is high
Small worlds
Decentralized search
Power law graphs
D. Easley and J. Kleinberg, Networks, Crowds, and Markets, Cambridge U. Press, 2010
Lecture Notes
Feb 19
Graph Sparsification
Random sampling algorithm of Karger
Spanners and cut sparsifiers
Benczur and Karger,  Randomized Approximation Schemes for Cuts and Flows in Capacitated Graphs, STOC 2002
Nick Harvey's notes
Lecture Notes
Feb 23
Graph Sparsification
Cut sparsifier using connectivity
Fung, Hariharan, Harvey, and Panigrahi, A general framework for graph sparsification, STOC 2011
Debmalya Panigrahi's notes
Lecture Notes
(same as above)
Feb 26
Graph Sparsification
Spectral sparsifiers
Spielman and Srivastava, Graph Sparsitication by Effective Resistances, SICOMP 2011
Nick Harvey's notes
Lecture Notes
Mar 1
Graph Sparsification
Spectral sparsifiers, contd
Lecture Notes
Mar 4
Streaming
Models, sampling methods
Frequent elements (Misra-Gries)
Amit Chakrabarti's notes
Lecture Notes
Mar 8
Spring Break

Mar 11
Spring Break

Mar 15
Streaming
Distinct elements (Alon-Matias-Szegedy)
Amit Chakrabarti's notes
Lecture Notes
Mar 18
Streaming
Frequency moments
Alon, Matias, and Szegedy, The space complexity of approximating the frequency moments, JCSS 1999

Mar 22
Streaming
Graph streaming: connectivity, spanning trees
Andrew McGregor, Graph stream algorithms: A survey, ACM SIGMOD Record, 2014

Mar 25
Embedding
Distance-based embedding into trees
Fakcharoenphal, Rao, and Talwar, A Tight Bound on Approximating Arbitrary Metrics by Tree Metrics, JCSS 2004
Elkin, Emek, Spielman, and Teng, Lower-Stretch Spanning Trees, SICOMP 2008
Avner Magen's notes
Chandra Chekuri's notes

Mar 29
Embedding
Cut-based embedding into trees
Räcke, Optimal Hierarchical Decompositions for Congestion Minimization in Networks, STOC 2008

Apr 1
Rounding of Linear Programs
Edge-disjoint paths; multicommodity flow
Randomized rounding
Williamson and Shmoys, The Design of Approximation Algorithms, Cambridge U. Press

Apr 5
Rounding of Semi-Definite Programs
Goemans and Williamson on Max-Cut
Williamson and Shmoys, The Design of Approximation Algorithms, Cambridge U. Press

Apr 8
The Primal-Dual Paradigm
Steiner network design
Williamson and Shmoys, The Design of Approximation Algorithms, Cambridge U. Press

Apr 12
The Primal-Dual Paradigm
Apr 15
The Multiplicative Weight Update Method
Arora, Hazan, and Kale, The Multiplicative Weights Update Method: A Meta-Algorithm and its Applications, Theory of Computing 2012

Apr 19
No class

Apr 22
Project Presentations
Apr 26
Project Presentations