location-independence in mobile computing

peter honeyman

center for information technology integration
the university of michigan
ann arbor

mobile distributed services
  • location transparency
  • mobilizing applications makes them location-aware
  • robust file system mobilizes vanilla applications
    sources of network traffic
  • client reads
  • client writes
  • cache consistency maintenance
    avoiding network traffic
  • delayed write
  • optimistic replication
  • fail on cache miss
    modes of operation
    connected partially connected fetch-only disconnected
    method normal operation delayed writes optimistic replication abort on cache miss
    network requirements continuous, high b/w continuous on-demand none
    where office local dialup or PCS ISDN, cellular, or long-distance anywhere
    issues
  • log optimization
  • log replay
  • networking
  • pre-heating
  • application adaptation
    log optimization and replay
  • optimization eliminates 50% - 75%
  • early replay promotes sharing
  • background replay daemon
    networking
  • replay packets interfere with interactive
  • adapt vj fast queue
  • lottery scheduling
    more networking
  • mobile ip
  • link layer agent
  • service bindings
    preheating a cache
  • hoarding
  • more elaborate schemes
  • overheating
    application adaptation
  • MH example
  • Odyssey
    availability
  • contact info@citi.umich.edu
    last updated 3 january 1996