Flexible analysis of distributed protocol implementations using virtual time

Analyzing the run-time behavior of network protocol implementations in a distributed setting is difficult. However, such analyses are both vital for assuring their functionality and for performance optimizations. Common debuggers typically do not facilitate the inspection of the global state of a protocol implementation that is distributed among several hosts. In this paper we present a virtual machine (VM) based approach for the analysis of distributed protocol implementations. From each of the VMs we extract local state information of choice. By consolidating a global soft-state based on this information and by providing the virtual machines with a virtual and logical progression of time, we facilitate the flexible analysis of x86-based implementations in a distributed fashion.