Evaluating Super Node Selection and Load Balancing in P2P VoIP Networks Using Stochastic Graph Transformation

  • Ajab Khan
  • Reiko Heckel
Part of the Communications in Computer and Information Science book series (CCIS, volume 314)


Super nodes have been introduced to improve the performance of structured P2P networks. The resulting heterogeneity benefits efficiency without compromising the decentralised nature. However, this only works as long as there are enough super nodes and the distribution of clients among them is roughly even. With the increase in the number of users or organisations preventing the use of their clients as super nodes, the overall number of candidate super nodes is limited. Thus selection and load balancing strategies are critical, especially in voice-over-IP (VoIP) networks where poor connectivity results in immediate loss of audio quality.

To evaluate different strategies we model the dynamics of P2P systems by graph transformations, a visual rule-based formalism supported by stochastic simulation. Considering P2P VoIP applications such as Skype, we model two alternative strategies one with static super node selection and load balancing and one based on dynamic selection and promotion, and compare their performance in ensuring client satisfaction.


P2P VoIP networks Load balancing Static and dynamic super node selection Stochastic modelling and simulation Graph transformation 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Ajab Khan
    • 1
  • Reiko Heckel
    • 2
  1. 1.Department of Computer ScienceUniversity of MalakandPakistan
  2. 2.Department of Computer ScienceUniversity of LeicesterU.K.

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