We have proposed the use of dynamically priced network services to provide QoS guarantees within a network. End-to-end QoS can be achieved by using several of these services, perhaps from different ISPs. In this paper we consider the problem of determining the bandwidth to allocate each service in order to maximize revenue, assuming that a single ISP can estimate the demand curves for each of its services. We develop and analyze two heuristics which provide time versus revenue tradeoffs. To determine the optimality of our solutions, we map the optimal allocation problem into a multiple choice multidimensional knapsack problem that approaches optimality as we increase the number of bandwidth allocation choices for each service. Our first heuristic, IterLP, achieves revenue close to 99% of the optimal solution, achieving this result in a very short time. The second heuristic, IterGreedy, achieves approximately 93% optimality, but executes more quickly than IterLP.

We have previously proposed the use of dynamically priced network services to provide QoS guarantees within a network. End-to-end QoS can be achieved by concatenating several of these services from different ISPs. In this paper we consider the problem of a single ISP determining the optimal paths on which to route each service within its network, as well as the optimal bandwidth to allocate to each service, in order for the ISP to maximize its revenue. We assume that the ISP can estimate the demand functions for each service. We define three heuristics: service grouping, iterative bottleneck avoidance, and iterative bottleneck avoidance with tabu. We demonstrate that iterative bottleneck avoidance with tabu achieves approximately 98% of an optimal solution.

Dividing a video into many segments and caching a certain amount of prefix data at the proxy from these segments, one prefix from each segment, are very useful mechanisms to provide interactive playback modes to the clients in a scalable streaming system. However, creating the appropriate segments and choosing an appropriate segmentation algorithm are daunting tasks. In this paper, we have proposed an on demand segmentation mechanism for scalable and interactive streaming systems. We propose that the proxy start with a non-segmented video and with a single prefix. The proxy then gradually divides a video into many segments as it receives more interactive playback requests and caches the prefixes of these new segments. Consequently, segmentation and prefix caching at the proxy are done on demand and user's playback pattern determines the appropriate size and the position of a segment in a video. We provide simulation results to show the effectiveness of our proposed schemes

Most research in network pricing focuses on improving QoS for a single network. These approaches are not easily extensible to a set of interconnected networks, as the inter-ISP negotiations would be unwieldy. Our approach is to provide a general QoS-aware networking service. We first introduce the concept of QoS-transit services: transit services with QoS guarantees, where dynamic pricing is used to regulate demand on the associated links. After reviewing the structure of the Internet, and the locations of bottlenecks, we describe an architecture for delivering QoS across multiple networks using QoS-transit services. We describe the charging and routing frameworks, and detail how billing, metering, and policing can be achieved. Furthermore, we address security considerations, and discuss compatibilities with current network protocols. Finally, since we cannot expect all ISPs to offer QoS-transit services, we describe the concept of overlay ISPs: ISPs who provide QoS-transit services by controlling an overlay network

We have previously proposed the use of dynamically priced network services to provide QoS guarantees within a network. End-to-end QoS can be achieved by concatenating several of these services, perhaps from different ISPs. In this paper we consider the problem of a single ISP determining the bandwidth to allocate to each service, and on which path, in order to maximize revenue while guaranteeing end-to-end QoS. No knowledge of demand functions is assumed. Optimal allocation of bandwidth to services is first considered, where services are assumed to be routed on predetermined paths. We define the Iterative Allocation Adjustment heuristic, based on the concepts of tatonnement, which, through simulation, is shown to achieve over 95% of the optimal revenue for an ISP. We also examine how to value the links in the network to identify rerouting possibilities, or possible routes for new services, in order to improve the revenue of an ISP.

Abstract The Java platform has many characteristics that make it very desirable for integrated continuous media processing. Unfortunately, it lacks the necessary CPU resource management facilities to support quality of service (QoS) guarantees for soft real‐time multimedia tasks. In this paper, we present our new Java Virtual Machine, Q‐JVM, which brings CPU resource management to the Java platform. Q‐JVM is based on Sun's JVM version 1.1.5. It implements an enhanced version of the MTR‐LS algorithm in its thread scheduler. Combined with admission control that could be implemented in an application‐level resource manager, it is able to support QoS parameters such as fairness, bandwidth partitioning and delay bound guarantees, as well as the cumulative service guarantee. Our test results show that Q‐JVM is backward compatible with the standard JVM from Sun, has low scheduling overhead, and is able to provide QoS guarantees as specified. Copyright © 2003 John Wiley & Sons, Ltd.

The purpose of this work is to explore a few of the relationships between these two concepts. They developed more-or-less independently: the object concept emerged from work in process structuring and from work in programming languages. Meanwhile, independent and unrelated work was going on to define and construct operating systems suitable for distributed computing.

The authors present an extension to the work of I. Suzuki and T. Kasami (see Proc. 3rd Int. Conf. Distributed Compact Syst., p.365-70 (1982)), where a mutual exclusion algorithm uses a message called a token to transfer the privilege of entering a critical region among the participating sites. The proposed algorithm checks whether the token is lost during network failure, and regenerates it if necessary. The mutual exclusion requirement is satisfied by guaranteeing regeneration of only one token in the network. Failures in a computer network are classified into three types: processor failure, communication controller failure, and communication link failure. To detect failures, a time-out mechanism based on message delay is used. The execution of the algorithm is described for each type of failure; each site follows a rather simple execution procedure. Each site is not required to observe the failure of other sites or communication links.>

Two algorithms, control token transfer algorithm (CTTA) and regenerate, are proposed to realize mutual exclusion in a computer network environment using a resilient circulating token. The algorithm CTTA uses a message called token to transfer the privilege of entering a critical region among the participating sites. The algorithm regenerate checks whether the token is lost during system failures, and regenerates it if necessary. Failures in a computer network are classified into three types. The execution of these two algorithms is described for each type of system failure. To detect system failures, a time-out mechanism based on message delay is used.>

In this work, we present the overall structure of DAME, which is an expert system capable of configuring and designing customized microprocessor based systems from original specifications.

This paper describes design and implementation of an IPC model for a distributed software testbed Shoshin. The IPC model was designed to provide a reliable message communication among distributed processes and to support implementations of user level protocols for various applications. A multiprocess structure, which separates a link level and a transport level, has been used to provide a flexible protocol management. The basic performance of the current implementation and the extensibility of the model are also discussed.

CCITT has proposed Recommendation X.75 as a technique for interconnecting public data networks in a standard way. However, this is not the only or necessarily the best approach. This paper focuses on two major factors in determining the merits of different network interconnection approaches, and compares the X.75 approach to a few alternatives in each of these areas.

This paper presents some of the lessons that we have learned from programming in a message-switched environment, and from the Mininet project in particular. We consider the issues of task programming versus monolithic programs, task invocation versus function call/return, and blocking and non-blocking message-passing primitives.

It is argued that the data-base of a nation-wide organization will exhibit geographic locality of reference. That is, most of the transactions homing on a given component of the data base originate from a particular geographic region. At the same time there is a need to operate the collection of components as a single data base to provide for occasional transactions which cross regional boundaries, and for managerial queries and retrieval operations that span the entire data base. There are several examples of this associated with business and industry: credit and inventory records for exmple.