The Role of Trace Modulation in Building Mobile Computing Systems

M. Satyanarayanan and Brian Noble


In this paper we put forth the view that trace modulation is an indispensable technique for building and evaluating mobile computing systems. The essence of our solution is transparent, real-time, trace-driven emulation of a target network. Although conceptually simple, trace modulation strikes an attractive balance between the conflicting demands of realism, ease-of-use, and reproducibility. It provides three important benefits. First, it allows control of the complexity of the network environment to which mobile software is exposed. Second, it enables mobile clients to be subjected to reproducible yet realistic network performance. Third, it allows easy exploration of a mobile system in the context of hypothetical mobility patterns and network infrastructures. These benefits suggest that trace modulation will play a central role in the development of future mobile computing systems.