Hot swapping technology combined with pervasive heterogeneous networks empowers mobile laptop users to select the best network device for their current environment. Unfortunately, the majority of systemsoftware remains "customized"for a particular network configuration, and assumes that many characteristics associated with the network environment remain invariant over the runtime of the software. Mobility causes changes in the environment and nullifies many of these assumptions. This leads to severe loss in system functionality when resources are lost, and failure to benefit when resources are gained. This paper describes Physical Media Independence (PMI), an architecture for dynamically diverse network interface management. PMI addressesthree issuesconcerningdynamicnetwork configuration. First, a model for device availability is proposed to accurately determine when a network device is operational. Second, a structured methodology is used to construct adapters that reconfig...