9. Chapter 9: Peer-to-peer networks

9.3. Application architectures

Client-server architecture 

Pure P2P architecture

Hybrid of client-server and P2P

Skype

  • voice-over-IP P2P application
  • centralized server: finding address of remote party: 
  • client-client connection: direct (not through server) 

Instant messaging

  • chatting between two users is P2P
  • centralized service: client presence detection/location
    • user registers its IP address with central server when it comes online
    • user contacts central server to find IP addresses of buddies

Process: program running within a host.

  • within same host, two processes communicate using  inter-process communication (defined by OS).
  • processes in different hosts communicate by exchanging messages

  • Note: applications with P2P architectures have client processes & server processes