Lecture 4: Groups

Terms you should know

Paul Krzyzanowski

February 28, 2021

Group communication

  • Uicast
  • Anycast
  • Broadcast
  • Multicast
  • Multicast groups
  • Open vs. closed groups
  • Peer vs. hierarchical communication
  • Coordinator
  • Unreliable multicast
  • Reliable multicast
  • Atomic multicast
  • Optimizations:
    • Pipelining
    • Cumulative acknowledgements
    • Piggybacked acknowledgements
    • Negative acknowldgements
  • Message receipt vs. delivery
  • Hold-back queue
  • Global time ordering
  • Total ordering
  • Causal ordering, partial ordering
  • Sync ordering
  • Single source FIFO ordering
  • Unordered multicast
  • Totally sequenced message IDs
  • Precedence vector (what it does, don’t memorize the algorithm)
  • Barrier

IP Multicast

  • IP multicast address (purpose)
  • Host group
  • Properties
  • IGMP: Internet Group Management Protocol
    • Membership query
    • Membership report
    • Leave group
  • IGMP vs. PIM (Protocol Independent Multicast)
  • PIM-DM - Dense Mode
  • PIM-SM - Sparse Mode
  • Rendezvous Point (RP)

Virtual Synchrony

  • State machine replication (the concept)
  • Stale state
  • Process group
  • Synchronous vs. asynchronous networks
  • Two armies problem
  • Group view
  • View change
  • Group Management Service (GMS)
  • Stable vs. unstable messages
  • Flush message
  • State transfer
Last modified February 28, 2021.
recycled pixels