overlay (and p2p) networks...barabási, albert-lászló, and réka albert. "emergence of...
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![Page 1: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/1.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Overlay (and P2P) Networks
● Complex Networks
● Applications of Overlay networks
● Advanced Topics
● Summary
Samu Varjonen
Ashwin Rao
Part II
![Page 2: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/2.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Schedule
● Complex Networks 11.02
● Complex Networks 15.02
● Complex Net & Apps 18.02
● Applications 22.02
● Advanced Topics 25.02
● Conclusion Summary 29.02
● Why Complex Networks?● Scale Free & Small World● Zipf's law● Power Law● Search in Small World
● Internet Indirection Infrastructure (I3)
● Content Delivery Networks● Dynamo ● SDN and Clouds
Any suggestions for advanced topics?
![Page 3: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/3.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
1) Hop-by-Hop -> Overlay
MACIP
TCP
MACIP
MACIP
MACIP
![Page 4: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/4.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
1) Hop-by-Hop -> Overlay
MACIP
TCP
MACIP
MACIP
MACIP
![Page 5: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/5.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
2) Peer-to-Peer
● Overlays (End-to-End Systems)
● Peer-to-Peer: example of an overlay system
● Peer
– An End in an End-to-End system
● All peers are ”end-systems”, but all ”end-systems” are not peers
– A computer, an end-user, an application depending on the context
Overlay Networks P2P
![Page 6: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/6.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
3) Unstructured Networks
● Flat or heirarchical organization
● Napster
● Gnutella
● Skype
● BitTorrent
● Freenet
![Page 7: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/7.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Napster (simple file sharing)
Centralized Directory Server
Client (A)
Client (B)
Client (C)
I hav
e Fi
le1,
File
2, ..
.
I have File2, File3, ...
I have File1, File3, ...
![Page 8: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/8.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Napster (simple file sharing)
Centralized Directory Server
Client (A)
Client (B)
Client (C)
A→ File1, File2,...B→ File2, File3,...C→ File1, File3,...
File 3
![Page 9: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/9.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
QHA
B
C
D E
Q
Q
Q
Q
Q Q QH
Gnutella (file sharing-old version)
![Page 10: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/10.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
QHA
B
C
D E
Q
Q
Q
Q
Q Q QH
Gnutella (file sharing-old version)
![Page 11: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/11.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Skype (P2P voice/video communication)
Directory Server
Super Nodes
![Page 12: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/12.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
BitTorrent(P2P content dissemination)
Tracker
Seed
File
Leecher
Leecher
File
File
![Page 13: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/13.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Freenet
● Self-organizing and Self-contained P2P network
● Collaborative (distributed) virtual file system
● Strong anonymity and censorship resistance
![Page 14: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/14.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
More Resources
● Video: Freenet at C3 Conference:
● B. Cohen. Incentives for building robustness in BitTorrent
● Stefan Saroiu, Krishna Gummadi, and Steven Gribble.”A Measurement Study of Peer-to-Peer File Sharing Systems.”
![Page 15: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/15.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Properties of Unstructured Overlay Networks
● Unstructured Link Creation
● Random Arrivals and Churn
● Flat or Hierarchical organization
● and many more …
![Page 16: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/16.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Why is modeling important?
● What is the expected latency to the peek the content?
– Average distance between nodes
● What is the impact of a peer leaving the network?
– Robustness to faults/down-times
● What are the factors that determine the evolution of the graph structure?
– Impact of proposed optimizations such as localization of content
● …
![Page 17: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/17.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Small World
● Stanley Milgram. "The small world problem." Psychology today 2.1 (1967): 60-67
”Given any two persons in the world, person X and person Z, how many intermediate acquaintance links are needed before X and Z are connected?”
● Mathematical structure of society
![Page 18: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/18.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Milgrams Approach
A random person X was selected and given a document.
The document contained
(1) The name of person Z and some information such as profession and city name
(2) If X did not know person Z then X mails it to a person Y whom X knows on a first name basis and who is more likely than X to know Z. (Y is the new X)
(3) A roster on which each person to whom document arrives writes his/her name. Roster also prevents endless looping.
![Page 19: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/19.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Key Result
Stanley Milgram. "The small world problem." Psychology today 2.1 (1967): 60-67
● Median: 5 intermediaries
– How many degrees of separation?
● Decay in active chains
– 126 of 160 chains dropped out!
● Common pathway
– Stock broker, clothing merchant
● Misc
– Role of gender, ethnicity
● When will two sub-populations be isolated from each other?
![Page 20: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/20.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Key Result
Stanley Milgram. "The small world problem." Psychology today 2.1 (1967): 60-67
● Median: 5 intermediaries
– How many degrees of separation?
● Decay in active chains
– 126 of 160 chains dropped out!
● Common pathway
– Stock broker, clothing merchant
● Misc
– Role of gender, ethnicity
● When will two sub-populations be isolated from each other?
![Page 21: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/21.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Random Graph( Erd s–Rényi)/Gilbert Modelő
![Page 22: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/22.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Modeling the ”Small World”
● Duncan Watts and Steven H. Strogatz. "Collective dynamics of ‘small-world’ networks." Nature 393.6684 (1998): 440-442.
– Diameter: length of the longest path
– Clustering Coefficient: how close are the adjacent vertices of a vertex to a complete graph (clique) if the vertex is removed.
– Desirable properties: Small Diameter and High Clustering Coefficient
![Page 23: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/23.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Random Rewiring Procedure
p=0 p=1(p=0.15)
n: number of verticesk: degree of each node, i.e., neighbours of a vertex (n >> k >> ln(n) >> 1) p: probability of rewiring
n=10, k=4
Large diameterHigh Clustering
Small diameterHigh Clustering
Small diameterLow Clustering
![Page 24: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/24.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Path Length L(.) and Clustering Coefficient C(.) in Rewired Graphs
n=1000, k=10
Duncan Watts and Steven H. Strogatz. "Collective dynamics of ‘small-world’networks." nature 393, no. 6684 (1998): 440-442.
![Page 25: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/25.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Is Small-World Networks the right model?
● What happens in dynamic networks whose members/vertices change with time?
● With which vertices of a graph do new arrivals prefer to attach?
● Is the the development of large networks governed by a robust self-organizing phenomena?
● What about heterogeniety in type of elements in and the degree distribution?
● …
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11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
What about degree distribution?
● Do small-world/random-graph models capture the presence of hubs?
AS Topology of skitter dataset parsed by SNAP team http://snap.stanford.edu/data/as-skitter.html
![Page 27: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/27.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Assumptions of Random Graphs and Small-World
● Fixed number of nodes that are either randomly connected (Random Graphs) or randomly rewired (Small-World)
● Probability that two vertices are connected is random and uniform
Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512.
![Page 28: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/28.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Scale Free Networks
● Probability that a node has k links is
● exponent for the degree distribution
● Why the name Scale-Free?
– Same functional form across all scales
● e.g. = 1 P(x) = 1/x→
● - is the slope on log log scale
![Page 29: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/29.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Preferential Attachment (Growth in Scale-Free Network)
● Initial number of nodes m0
● At time 't' add a new vertex j with degree m (< m0)
● The probability that vertex j creates a link with vertex i is the probability π which depends on ki (the degree of
vertex i)
● Probability that a node has k links is
● exponent for the degree distribution
Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512.
![Page 30: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/30.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Scale-Free Model for AS-Graph
= 2.18
AS Topology of skitter dataset parsed by SNAP team http://snap.stanford.edu/data/as-skitter.html
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11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Scale Free for Gnutella?
Gnutella August 2002 dataset parsed by SNAP team http://snap.stanford.edu/data/p2p-Gnutella31.html
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11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Summary
● Large number of interacting elements
● System adapts and evolves
● Although elements follow simple rules, the system behaves in a complex manner
● System behavior is an outcome of the interaction between the elements, so studying elements in isolation will not provide detailed insights on system behavior
● Similar processes shape networks therefore many networks share similar characteristics
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11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Methodology
1)Make observations (conduct measurement studies)
2)Build model to explain observations
– Choose the right level of granularity (zoom level)
– Strip the problem to a simple form
– Attempt to formulate the problem and model the system
3)Validate model
– Reproduce observations/measurements
– Explain observations
4)Revisit step 2 (and 1) to improve understanding
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11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Overlay Networks
P2POverlay Networks
Complex Networks
![Page 35: Overlay (and P2P) Networks...Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512. Albert, Réka, and Albert-László](https://reader035.vdocuments.net/reader035/viewer/2022071511/6130b7af1ecc51586944465b/html5/thumbnails/35.jpg)
11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Important Papers
● Stanley Milgram. "The small world problem." Psychology today 2.1 (1967): 60-67
● Duncan Watts and Steven H. Strogatz. "Collective dynamics of ‘small-world’ networks." Nature 393.6684 (1998): 440-442.
● Barabási, Albert-László, and Réka Albert. "Emergence of scaling in random networks." Science 286, no. 5439 (1999): 509-512.
● Albert, Réka, and Albert-László Barabási. "Statistical mechanics of complex networks." Reviews of modern physics 74.1 (2002): 47.
● Mitzenmacher, M. (2004). "A brief history of generative models for power law and lognormal distributions." Internet mathematics, 1(2), 226-251.
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11.02.2016
HELSINGIN YLIOPISTOHELSINGFORS UNIVERSITETUNIVERSITY OF HELSINKI
Faculty of SciencesDepartment of Computer Science Overlay (and P2P)
Sources for these slides
● Sasu Tarkoma ”Overlay and P2P Networks”, 2015● Arnaud Legout. ”Peer-to-Peer Applications : From
BitTorrent to Privacy”, January 2012.● Jari Saramäki ”Introduction to Complex Networks”,
2010.● Datasets from Stanford Network Analysis Project
(SNAP)