Charles Krasic

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This paper presents a general design strategy for streaming media applications in best effort computing and networking environments. Our target application is video on demand using personal computers and the Internet. In this scenario, where resource reservations and admission control mechanisms are not generally available, effective streaming must be able(More)
The Internet's ubiquity amply motivates us to harness it for video distribution, however, its best-effort service model is in direct conflict with video's inherent timeliness requirements. Today, the Internet is unrivaled in its rich composition, consisting of an unparalleled assortment of networks and hosts. This richness is the result of an architecture(More)
This paper presents an experimental study of the latency behavior of the Linux OS. We identify major sources of latency in the kernel with the goal of providing real-time performance in a widely used general-purpose operating system. We quantify each source of latency with a series of micro-benchmarks and also evaluate the effects of latency on a(More)
The dominance of the TCP protocol on the Internet and its success in maintaining Internet stability has led to several TCP-based stored media-streaming approaches. The success of these approaches raises the question whether TCP can be used for low-latency streaming. Low latency streaming allows responsive control operations for media streaming and can make(More)
In this paper we explore the use of Priority-progress streaming (PPS) for live video streaming applications with tight latency constraints. PPS is a technique for the delivery of continuous media over variable bit-rate channels. It is based on the simple idea of reordering media components within a time window into priority order before transmission. The(More)
Specialization is a growing area of interest in the operating systems community. OS components specialized to some particular circumstance can o er enhanced performance, functionality, or both. Complimentary partial evaluation techniques for automatically specializing programs are also reaching maturity. However, the problem of managing specialization(More)
Commodity operating systems are increasingly being used for serving time-sensitive applications. These applications require low-latency response from the kernel and from other system-level services. In this paper, we explore various operating systems techniques needed to support time-sensitive applications and describe the design of our Time-Sensitive Linux(More)
The need for customizable and application-speci c operating systems has been recognized for many years. A customizable operating system is one that can adapt to some particular circumstance to gain some functional or performance bene ts. Microkernels have attempted to address this problem, but su er performance degradation due to the cost of inter-process(More)