Promoting Quality of Service in Substitution Networks with Controlled Mobility

International audienceA substitution network is a rapidly deployable backup wire- less solution to quickly react to network topology changes due to failures or to ash crowd e ects on the base network. Unlike other ad hoc and mesh solutions, a substitution network does not attempt to provide new services to customers but rather to restore and maintain at least some of the services available before the failure. Furthermore, a substitution net- work is not deployed directly for customers but to help the base network provide services to the customers. Therefore, a substitution network is not, by de nition, a stand-alone network. In this paper, we describe the quality of service architecture for substitution networks and discuss pro- visioning, maintenance, and adaptation of QoS inside and between the base network and the substitution network

The role of HiPPI switches in mass storage systems: A five year prospective

New standards are evolving which provide the foundation for multi-gigabit per second data communication structures. The lowest layer protocols are so generalized that they encourage a wide range of application. Specifically, the ANSI High Performance Parallel Interface (HiPPI) is being applied to computer peripheral attachment as well as general data communication networks. The HiPPI Standards suite and technology products which incorporate the standards are introduced. The use of simple HiPPI crosspoint switches to build potentially complex extended 'fabrics' is discussed in detail. Several near term applications of the HiPPI technology are briefly described with additional attention to storage systems. Finally, some related standards are mentioned which may further expand the concepts above

Grid-based Model for Recovery of Lost Connectivity in Wireless Sensor and Actor Network

Wireless Sensor and Actor Networks (WSAN) are basically a collection of actors and sensors collaborating via a wireless medium to perform designated tasks. Maintaining inter-actor connectivity is critical to a WSAN, as failure at one point may result in communication loss amongst nodes or in a network disjoint. To recover from an actor node failure, optimal re-localization and coordination techniques should be in place. However, existing recovery schemes suffer from high degrees of actor node relocation overhead as well as network overhead. In this paper, we introduce a Grid-based Mathematical Model for efficient Actor Recovery by Determining Forwarding Capacity (GMMFC). The proposed model aims to provide effective monitoring and actor failure detection mechanism supported by an efficient actor recovery algorithm. GMMFC presents an innovative concept in actor node recovery while proposing improvements in WSAN QoS performance using RSSI Message information. The proposed solution is compared with state-of-the-art algorithms. The experimental results manifest better performance over delay, throughput, packet delivery ratio, energy consumption as well as for messages exchanged between sensor and actor nodes. Thus, the proposed model demonstrates improvements in QoS parameters

Aviation technology research plan rotary wing program development and evaluation of performance

Issued as Progress reports [nos. 1-2], and Final report, Project no. E-16-M08Final report has title: Aviation technology research plan rotary wing program development and evaluation of performanceFinal report has co-author: J.V.R. Prasa

On the Impact of Routers' Controlled Mobility in Self-Deployable Networks

International audienceA substitution network is a temporary network that self-deploys to dynamically replace a portion of a damaged infrastructure by means of a fleet of mobile routers. In this paper, we evaluate the performance of a previous self-deployment scheme, adaptive positioning algorithm (APOLO), for substitution networks and we show the benefit of the controlled mobility in such a network. To that end, we evaluate APOLO in terms of throughput under several scenarios and different metrics. These results constitute a comprehensive evaluation of APOLO and enable to envision new ways of optimization and future paths of research. We prove that APOLO is an efficient deployment and redeployment algorithm for mobile relay networks

The creation and early implementation of a high speed fiber optic network for a university health sciences center

pre-printIn late 1989 the University of Missouri Health Sciences Center began the process of creating an extensive fiber optic network throughout its facilities, with the intent to provide networked computer access to anyone in the Center desiring such access, regardless of geographic location or organizational affiliation. A committee representing all disciplines within the Center produced and, in conjunction with independent consultants, approved a comprehensive design for the network. Installation of network backbone components commenced in the second half of 1990 and was completed in early 1991. As the network entered its initial phases of operation, the first realities of this important new resource began to manifest themselves as enhanced functional capacity in the Health Sciences Center. This paper describes the development of the network, with emphasis on its design criteria, installation, early operation, and management. Also included are discussions on its organizational impact and its evolving significance as a medical community resource

GRTS operations monitor/control system

An Operations Monitor/Control System (OMCS) was developed to support remote ground station equipment. The ground station controls a Tracking Data Relay Satellite (TDRS) relocated to provide coverage in the tracking system's zone of exclusion. The relocated satellite significantly improved data recovery for the Gamma Ray Observatory mission. The OMCS implementation, performed in less than 11 months, was mission critical to TDRS drift operations. Extensive use of Commercial Off The Shelf (COTS) hardware and software products contributed to implementation success. The OMCS has been operational for over 9 months with no significant problems. This paper will share our experiences in OMCS development and integration