Leveraging Smart Phones to Reduce Mobility Footprints

Stephen Smaldone, Benjamin Gilbert, Nilton Bila, Liviu Iftode, Eyal de Lara, M. Satyanarayanan

International Conference on Mobile Systems, Applications, and Services (MobiSys), Kraków, Poland, June 2009



Mobility footprint refers to the size, weight, and energy de- mand of the hardware that must be carried by a mobile user to be e ective at any time and place. The ideal of a zero mobility footprint is achievable by encapsulating per- sonal computing state in a virtual machine (VM) and de- livering it over the Internet to a locally-obtained computer close to the user. In locations with poor Internet connectiv- ity, the demands placed on WAN bandwidth can result in unacceptable user experience. We show how this challenge can be overcome by using nascent smart phone technology as a trusted personal assistant called Horatio that serves as a self-cleaning portable cache for VM state. Since most users already carry cell phones for voice calls and texting, Hora- tio does not increase the size or weight aspects of a user's mobility footprint | there is only a small increase in the energy aspect. We have built an experimental prototype of Horatio, and measurements con rm its ability to improve user experience even with current smart phone limitations.