Michael Levi Fraenkel

InVerse: Designing an interactive universe architecture for scalability and extensibility

Faster networks, faster processors, and standardized protocols have enabled the emergence of interactive applications running over commercial networks such as the Internet. In such applications, multiple users interact with one another by exchanging real-time information such as user position and orientation in a virtual world, live and recorded audio, video, and text. These applications include interactive shopping, team training, virtual meeting rooms, and multi-player games. However, to date, these interactive systems have supported a limited number of information types, offered limited scalability, and have failed to account for a heterogeneous network and processor environment. In this paper, we describe the design and implementation of InVerse, an infrastructure that supports real-time interactive applications on the Internet. InVerse provides a common backplane for disseminating and managing multiple real-time data streams. Within this general-purpose structure, the InVerse system maximizes scalability by implementing a hybrid communications architecture that adapts itself to available network bandwidth, observed network latency, installed network security measures, and available services such as multicast.

Building high-performance applications and services in Java: an experiential study

Java is the programming language of choice for dynamic content on the hternet The language’s popularity has arisen from its portability, ease-ofaad integration with HThE.. Java is used to enable animation on Web pages, to dynamically select and format Web page content at IV& sxvers, and to provide clientside user input checking as a iiunt-end to tmnsaUion-orieuti applications. However, with a few exceptions, Java has not been used to develop applicatioas and servers that demand high performance or throughpnt In this paper, we desxii techniques for improving the performance of Java code and enabling the development of high-throughput appkations and servers. We show that Java code can be easiIy optimki to achieve performance that is comparable with that of tmditional languages such as C or C+i. We base these resuks on oar experience in developing the Inverse @n&active Universe) server in Java. Our resolts apply to Sun’s Java class library and virtual machine, but other implementations may exhibit other performance chamctedstics.