Operating system support for distributed multimedia

We have been investigating an end system architecture to support networking with quality of service guarantees. For user level protocol code in our architecture: to access the network, we have designed a kernel-user interface. The interface targets three areas for improvement: reduced copying, reduced reliance on explicit kernel-user interactions, and provision of rate-based flow control. In this paper, we present the concept of input-output efficient buffers for reduced copying, the concept of fast system calls for low-latency network access, and the concept of kernel threads for flow central. Also included is a concept called direct media streaming which is suitable for applications that require limited user processing of media data. These concepts have been implemented as an extension to SunOS 5.3 (the operating system component of Solaris 2.3). We report some experimental results on the performance of our current system. (C) 1998 John Wiley & Sons, Inc.