1 / 6

Researcher M.Sc. Mikko Vapa University of Jyväskylä Agora Center mikvapa@jyu.fi

Power-law Networks InBCT 3.2 Peer-to-Peer communication Cheese Factory -project http:// tisu .it.jyu.fi/ cheesefactory. Researcher M.Sc. Mikko Vapa University of Jyväskylä Agora Center mikvapa@jyu.fi. Highway map. Flight map. Maps and their route distribution.

khuyen
Download Presentation

Researcher M.Sc. Mikko Vapa University of Jyväskylä Agora Center mikvapa@jyu.fi

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Power-law NetworksInBCT 3.2 Peer-to-Peer communicationCheese Factory -projecthttp://tisu.it.jyu.fi/cheesefactory Researcher M.Sc. Mikko VapaUniversity of Jyväskylä Agora Center mikvapa@jyu.fi

  2. Highway map Flight map

  3. Maps and their route distribution • Highway routes follow normal distribution: • But because of hubs like Helsinki flight routes have different characteristics. This structure is called power-law distribution: γ = degree exponent

  4. Power-law structured network • Power-law network of 50 nodes • Nodes 1, 2, 3 and 4 are the most visible hubs

  5. History of Power-law Networks • Despite that power-law networks have been out there since life was born they were just recently discovered (in 1999 World Wide Web was found to be a power-law network) • In a short time many other network maps were found to follow power-law distribution: • Internet routers and cables • Social networks (only 6 hops between any people in the world) • Companies (Nokia as a hub with many small subcontractors) • Molecules and chemical reactions in living organisms (H2O, ATP, ADP and CO2 molecules as hubs) • Peer-to-peer networks (Gnutella diagnosed as the first one) • During years 2000-2002 researchers came into a conclusion that this structure is universal and dominates all forms of life and organisation in complex systems and societies

  6. Characteristics of Power-law network • Fault-tolerant meaning that no matter how many nodes fail the network stays connected • Short network distance between any node in the network meaning that searching can be done efficiently • Still unclear: • How do these networks emerge? • research on evolution of networks is needed • What is the most efficient way to search these networks? • new search algorithms are needed • Reference: Barabási, A.-L., ”Linked – The New Science of Networks”, Perseus Publishing, 2002 EUROOPAN UNIONI

More Related