Enterprises nowadays are approaching towards an all IP paradigm by subscribing to different access technology links from several service providers for reliability and redundancy while providing good Quality of Service (QoS). Global System for Mobile Communications (GSM) to Voice over IP (GSM-2-VoIP) convergence and vice-versa is a step forward towards this unification goal. It requires dynamic routing between IP, digital, analog and GSM networks. A decisionmaking framework is presented that can handle both the dynamic routing decision computation at private-public network border for inbound/outbound calls (GSM-2-VoIP) and the horizontal handover decision-making among various GSM cells. The decision engine takes multiple criteria into account while computing the routing and/or handover decisions (attributes from context of the request, platform's latest conditional parameters, business objectives of the company etc.) and/or (mobility management issues, user profile, traffic load etc.) respectively. An all open source real time platform consisting of Universal Serial Radio Peripheral (USRP), GNU Radio, an extended GSM stack (OpenBTS), OpenSIPS and Asterisk is developed to validate the proof of the concept. The system gives higher throughput and lower call dropping probability with an add-on susceptible delay offering good QoS and lower cost.

Abstract-A framework for rule-based multimedia network management in multihoming environment is presented. Information diversity with multiple criteria and semantic variations has led us to integrate the Multi Criteria Decision Making (MCDM) theory and Ontology over an all IP platform. MCDM helps in achieving the multiple objectives on the basis of multi-disciplinary information domains. The ontology, on the other hand, overcomes the semantic matching and reasoning issues using conventional object-oriented techniques with the help of inference engine. A simple use-case involving the dynamic decision-based routing at private-public network border is presented to validate the proposed solution. The system gives higher throughput and lower call dropping probability with an add-on susceptible delay offering good QoS.

WOSInternational audienceRemote sensing applications require developing accurate models to predict radar bistatic scattering from random rough surfaces. In this context, an improved two-scale model (TSM) is developed. The simplest TSM (TSM1) combines the first order small perturbation method (SPM1) with geometrical optics (GO) to be able to cope with both the small- and large-scale components of the surface. To get improved results at grazing angles and better depolarization estimation, we include the effects of multiscattering due to the target surface by adding the second order SPM (SPM2) contribution to SPM1 at small scale and develop an improved TSM (TSM2). The applications of TSM2 are presented for sea surface by assuming the surface-height spectrum of Elfouhaily et al., at grazing angles. In the backscattering configuration the numerical results are compared with the published experimental data and other approximate analytical models. Finally, we use the TSM2 to predict the sea scattering in the bistatic configuration and compare the results with TSM1

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