Gossip Algorithms over Different Network Topologies

A brief description of three different gossip algorithms (probabilistic broadcast, probabilistic edge and fixed fanout) with detailed examples on how do they work over different network topologies (Erdős–Rényi, random geometric graph and scale free).
June 20, 2017—Daniele Baschieri

Random Graph

Gossip algorithms are a system of machine-to-machine communication whose goal is to minimize channel usage and maximize the coverage of a network. The network can be seen as graph of nodes. Nodes represent computers, and edges represent connections.
An example of a random graph:
In[]:=
randomGraph=RandomGraph[{8,20}]
Out[]=
A pure broadcast mechanism sends the message to all the other nodes connected with the source. This method leads to a complete coverage of the message in the graph, but on the other hand causes saturation of the channel.
The source of the message is in red, with mail on the involved edges:
In[]:=
SetPropertySetProperty{randomGraph,EdgeList[randomGraph,1_]},EdgeLabels
,1,VertexStyleRed
Out[]=

Symbols and Functions

Probabilistic Broadcast

Probabilistic Edge

Fixed Fanout

Erdős–Rényi or Bernoulli Graph

Random Geometric Graph

Example of a Random Geometric Graph

Scale-Free Graph

Example of a Scale-Free Graph

Comparison between the Graph Topologies

Conclusion

FURTHER EXPLORATIONS
Graph Theory
Social Network
Torrent and Peer-to-Peer
Routing
AUTHORSHIP INFORMATION
Daniele Baschieri
6/20/17