Beyond audio and video: multimedia networking support for distributed, immersive virtual environments

Like interactive audio/video applications, distributed virtual environments (DVEs) require continuous, low-latency delivery of media. While end-system media adaptations and network-based forwarding services have been developed to support audio/video applications, it remains an open question whether these mechanisms can be either directly applied or adapted to realize the requirements of DVEs. We present the results of a study on the use of audio/video media adaptations and router-based active queue managements (AQM) to support the data-flows generated by the UNC nanoManipulator-a DVE interface to a scanned-probe microscope. We present a delay-jitter management scheme used to support a haptic force-feedback tracking/pointing device used in the nanoManipulator and an AQM scheme based on buffer allocation in routers to reduce packet loss. The results of early experiments are promising and provide evidence that a sophisticated virtual environment interface can operate over the Internet to control a remote microscope in real-time