36131867
Lambda GLSP setup with QoS requirements in optical Internet
GMPLS is currently being specified as the control plane for next generation optical networks. While one merit of GMPLS is that network operators are able to control the traffic of Internet Protocol (IP) and thus offer performance superior to that of traditional Internet Gateway Protocols (IGP), it has been a challenge to develop an efficient Traffic Engineering (TE) technique to satisfy the different traffic requirements of end-users in GMPLS domain. Several TE techniques have been thought of by creating a set of Generalized Label Switched Paths (GLSPs) in the optical network. In this paper we present a technique for establishing GLSP in optical Internet, that supports Quality of Service (QoS) considering the traffic flows with delay QoS requirements. This approach accounts for the processing delay at the network layer that may be encountered in optical nodes that terminate lightpaths and perform some types of traffic grooming. Additionally, we extend the QoS routing framework by defining additional extensions that can be used in conjunction with Shared Risk Group (SRG) identifiers to reserve backup paths that do not share network resources with the working paths that they are protecting. We provide some simulation results to demonstrate the effectiveness of our routing algorithms.
44827064
A MPLS-Based Micro-mobility Supporting Scheme in Wireless Internet
In this paper, we propose to exploit pre-established label switched paths with the aim to reduce handover processing latency which is one of the most critical performance metrics in micro-mobility environment. Thus, our proposed scheme has an advantage of offering micro-mobility to Mobile IP (MIP) with lower-latency handover as compared with the several existing MPLS-based MIP approaches. An analytic model of setting up LSPs for fast handover processing is presented. Further, we investigate the performance of our model.
18035365
A Web Service Approach to Universal Accessibility in Collaboration Services
The enormous growth in wireless communications and miniaturized handheld devices in the last few years, have given rise to a vast range of new services, for heterogeneous user environments. In this paper, we investigate the nature of designing distributed services that accommodate pervasive devices. We introduce Universal Accessible Web service architecture, CAROUSEL Web service. We present our collaborative Web services model linked with an event brokering service, NaradaBrokering. We discuss how a rich synchronous and asynchronous collaboration environment can support virtual communications while being built on top of a Web service infrastructure, based on industry standard portal technologies such as XML, Apache’s Jetspeed, and WSDL. The linkage of the event brokering system with a Web service based architecture is one of the critical design issues in message-based collaborative application. We also describe the approach to universal access mechanisms in our collaborative Web service model. Also included is a discussion of the prototype collaborative SVG (Scalable Vector Graphics) browser that we developed as a Web service.
14065201
An Accurate Instruction-Level Energy Consumption Model for Embedded RISC Processors
Energy consumption of software is becoming an increasingly important issue in designing mobile embedded systems where batteries are used as the main power source. As a consequence, recently, a number of promising techniques have been proposed to optimize software for reduced energy consumption. Such low-power software techniques require an energy consumption model that can be used to estimate or predict the energy consumed by software. We propose a technique to derive an accurate energy consumption model at the instruction level, combining an empirical method and a statistical analysis technique. The result of the proposed approach is given by a model equation that characterizes energy behavior of software based on the properties of the instructions. Experimental results show that the model equation can accurately estimate the energy consumption of random instruction sequences, with an average error of 2.5%
22132767
Analog on-chip-learning for active noise canceling
Abstract Active noise canceling is demonstrated by analog neuro-chips with on-chip learning capability. The developed neuro-chip faithfully incorporates the error-backpropagation learning rule. Without any digital signal processor the developed system successfully compensated for nonlinear distortion of loudspeakers as well as for acoustic multi-path fading and random noises in real time.
10953963
Ad Hoc Routing with Early Unidirectionality Detection and Avoidance
This paper is motivated by the observation that current research in ad hoc networks mostly assumes a physically flat network architecture with the nodes having homogeneous characteristics, roles, and networking- and processing-capabilities (e.g., network resources, computing power, and transmission power). In real-world ad hoc networks however, node heterogeneity is inherent. New mechanisms at the network layer are required for effective and efficient utilization of such heterogeneous networks. We discuss the issues and challenges for routing protocol design in heterogeneous ad hoc networks, and focus on the problem of quickly detecting and avoiding unidirectional links. We propose a routing framework called Early Unidirectionality Detection and Avoidance (EUDA) that utilizes geographical distance and path loss between the nodes for fast detection of asymmetric and unidirectional routes. We evaluate our scheme through ns-2 simulation and compare it with existing approaches. Our results demonstrate that our techniques work well in these realistic, heterogeneous ad hoc networking environments with unidirectional links.
14875367
Optical Flow Rendering
This paper proposes a new approach to image-based rendering that generates an image viewed from an arbitrary camera position and orientation by rendering optical flows extracted from reference images. To derive valid optical flows, we develop an analysis technique that improves the quality of stereo matching. Without using any special equipments such as range cameras, this technique constructs reliable optical flows from a sequence of matching results between reference images. We also derive validity conditions of optical flows and show that the obtained flows satisfy those conditions. Since environment geometry is inferred from the optical flows, we are able to generate more accurate images with this additional geometric information. Our approach makes it possible to combine an image rendered from optical flows with an image generated by a conventional rendering technique through a simple Z-buffer algorithm.