Among many P2P networks, BitTorent is very famous for sharing files over a network. In this chapter, we proposed modeling and simulation of the BitTorrent protocol by using a combination of agent-based and complex network-based approaches. The simulation results demonstrate that our proposed ABM-based BitTorrent model performedbetter. Furthermore, forABM specification, we followed two approaches, first is ODD and the second one is DREAM methodology. We presented qualitative as well as a quantitative comparison of both ODD and DREAM specification techniques. The comparative study of ODD and DREAM proved that DREAM methodology is the more useful approach for documenting an ABM not only in terms of modeling but also for replication of the models, specifically for P2P networks.

Chapter Contents:

• 11.1 Introduction
• 11.1.1 Contributions
• 11.2 Background and literature review
• 11.2.1 Complex adaptive systems
• 11.2.2 Modeling and simulation of CACOONS
• 11.2.2.1 Agent-based modeling
• 11.2.2.2 Cognitive agent-based computing
• 11.2.2.3 Complex network modeling
• 11.3 BitTorrent peer-to-peer protocol
• 11.3.1 BitTorrent history overview
• 11.3.2 Content publishing in BitTorrent
• 11.3.3 Joining swarm and peers discovery in BitTorrent
• 11.3.4 Delivery procedure BitTorrent
• 11.3.5 BitTorrent architecture and working
• 11.3.5.1 Peer
• 11.3.5.2 Swarm
• 11.3.5.3 Tracker
• 11.3.5.4 Leecher
• 11.3.5.5 Seeder
• 11.3.5.6 Mechanism and architecture
• 11.3.5.7 Limitations of BitTorrent
• 11.4 BitTorrent literature review
• 11.4.1 PeerSim
• 11.4.1.1 Scalability
• 11.4.1.2 Modularity
• 11.5 Model design
• 11.5.1 ODD approach
• 11.5.1.1 Entities, state variables and scales
• 11.5.1.2 Process overview and scheduling
• 11.5.1.3 Design concepts
• 11.5.2 Overview of the proposed model
• 11.5.2.1 Problem statement
• 11.5.2.2 Node agents
• 11.5.2.3 States of node agents
• 11.5.2.4 Activity diagrams
• 11.5.2.5 Sequence diagrams
• 11.5.3 DREAM model
• 11.5.4 Pseudocode-based specification
• 11.5.4.1 Agents and breeds
• 11.5.5 Globals
• 11.5.6 Procedures
• 11.5.6.1 Check-if-segment-is-available
• 11.5.6.2 Check-if-segment-is-needed-by-others
• 11.5.6.3 Do-plots
• 11.5.6.4 Generate-random-segment-number
• 11.5.6.5 Go
• 11.5.6.6 Make-turtles
• 11.5.6.7 Makes-new-seeds-green
• 11.5.6.8 Selfish-green-turtles-dropout
• 11.5.6.9 Setup
• 11.5.6.10 Upload-file-segment
• 11.5.7 Experiments
• 11.5.8 Results and discussions
• 11.5.8.1 Metrics table and description
• 11.5.9 PeerSim results
• 11.5.10 ABM results
• 11.5.11 Comparison of both
• 11.5.12 DREAM network models
• 11.5.12.1 Plots of centralities
• 11.6 Discussion (ODD vs DREAM)
• 11.7 Conclusion
• References

Inspec keywords: complex networks; peer-to-peer computing; protocols

Other keywords: Overview, Design concepts and Details; BitTorrent P2P protocol; protocol simulation; ODD model; complex network-based modeling; DREAM modeling; ABM-based BitTorrent model; peer-to-peer file-sharing protocol; P2P networks; descriptive agent-based modeling

Subjects: Protocols; Computer communications; Protocols; Internet software; Computer networks and techniques