Showing papers by "Kenneth L. Calvert published in 2001"

TCP/IP Sockets in C: Practical Guide for Programmers

Abstract: Most Internet applications use sockets to implement network communication protocols. TCP/IP Sockets in Java: Practical Guide for Programmers, with its focused, tutorial-based coverage, helps you master the tasks and techniques essential to virtually all client-server projects using sockets in Java. Later chapters teach you to implement more specialized functionality; incisive discussions of programming constructs and protocol implementations equip you with a deeper understanding that is invaluable for meeting future challenges. No other resource presents so concisely or so effectively the exact material you need to get up and running with Java sockets programming.

Concast: design and implementation of an active network service

Abstract: Concast is a network layer service that provides many-to-one channels: multiple sources send messages toward one destination, and the network delivers a single "merged" copy to that destination. As we have defined it, the service is generic but the relationship between the sent and received messages can be customized for particular applications. We describe the concast service and show how it can be implemented in a back ward-compatible manner in the Internet. We describe its use to solve a problem that has eluded scalable end-system-only solutions: collecting feedback in multicast applications. Our preliminary analysis of concasting effectiveness shows that it provides significant benefits, even with partial deployment. We argue that concast has the characteristics needed for a programmable service to be widely accepted and deployed in the Internet.

Active reliable multicast on CANEs: a case study

Abstract: This paper presents a case study in implementing a moderately complex, useful service on an active network platform. The active application is reliable multicast with congestion control; the platform comprises the Bowman Node Operating System and the Composable Active Network Elements (CANEs) Execution Environment. The importance of the work stems from the lessons it provides about the design and implementation of active platforms in general and Bowman/CANEs in particular. For example, our experience shows that timer-driven active node processing is as important as packet-arrival-driven processing. Thus, execution environments cannot focus exclusively on forwarding, but must also provide efficient timers and allow timer handlers the same capabilities as packet-driven computations. Other areas in which the implementation provides insight include service decomposition approaches for active applications and information sharing among service components.

Leveraging emerging network services to scale multimedia applications

Abstract: Multicast services have been used for many years to transmit multimedia data to large receiver groups. However, only recently have counterpart network services been introduced that provide similar scalability and anonymity in the opposite direction (i.e., messages from a group of senders destined for a common receiver). In this paper, we explore how these emerging services, specifically a concast service (many-to-one communication service), can be used to improve the scalability and performance of multimedia applications. In particular, we show how such services can be used in both the control and data planes to overcome well-known scalability problems (e.g., with RTP) that are difficult to solve effectively with end-system approaches alone. We validate our solutions by presenting experimental results taken from prototype video and audio applications we designed and implemented. Our initial results show a reduction of as much as two orders of magnitude in packet loss rates using these generic services.

Domain Name Service

Abstract: A Transmission Control Protocol (TCP)/Internet Protocol family uses numeric Internet addresses and numeric ports to describe communication endpoints. The host naming service can access information from a wide variety of sources. This makes the protocol implementations efficient, but has at least two drawbacks. First, strings of numbers do not mean much to humans and are therefore, hard to remember. And second, a host's Internet address is tied to the part of the network to which it is connected. This fosters inflexibility in their use. If a host moves to another network or changes Internet service providers (ISPs), in general, its Internet address must change. Two of the primary sources are the domain name system (DNS) and local configuration databases. Local configuration databases are generally operating-system-specific mechanisms for name-to-Internet-address mappings. The source of the information is implementation dependent and may be the DNS, a local configuration database, or some combination of the two. The application programming interface provides a way to obtain information about an application (server), including the port number it uses, by name.