Search results for " Network"
showing 10 items of 6428 documents
Secure interworking with P2PSIP and IMS
2010
In this paper, we propose a secure system model for interconnection between P2PSIP and IMS domains. The interworking solution is based on P2P-IMS GateWay (PIGW), which acts as a normal peer in P2PSIP network and a 3rd party IMS Application Server (AS) in IMS network. The security is achieved by implementing Chord Secure Proxy (CSP) and enhanced with subjective logic based trust model. We also implement this system model and analyze it in several aspects: number of hops and delay, trust improvement and protection against malicious or compromised intermediate peers. We conclude that the proposed architecture is feasible and improves security. As far as we know our research is the first study …
Trust enhancement of P2PSIP communication systems
2011
Today, peer-to-peer (P2P) session initiation protocol (SIP)-based communication systems have attracted much attention from both academia and industry. The decentralised nature of P2P might provide the distributed P2P communication system without help of the traditional SIP server. However, it comes to the cost of reduced trustworthiness and may cause security problems, e.g., privacy leaks, unpredictable availability, etc. In this paper, we investigate P2PSIP security issues and propose a subjective logic-based trust model that offers trust-based security services during P2PSIP session establishment. The main issues considered in this model include opinion calculation, opinion maintenance, d…
Transport service for session initiation protocol in SIP-T scenarios
2005
The traditional telephone service has undergone deep changes in the years concerning the techniques of commutation and signaling. Today, public switched telecom networks (PSTNs) and private integrated services networks (PINSs) are strongly directed to adopt IP-based backbone. If it is possible to transfer the voice on packet switching network, in such reliable way, using voice over IP (VoIP) techniques, there is not still a valid alternative to the signaling systems, reliable and unfailing, like signaling system n.7 (SST). Session initiation protocol (SIP) seems to be the best candidate. SIP is an application layer signaling protocol and the problem remains still opened for what it concerns…
Analysis and Simulation of the Signaling Protocols for the DiffServ Framework
2006
This paper considers signaling protocols for the DiffServ QoS framework. Originally, DiffServ had no standardized signaling solution, which resulted in the static configuration for the DiffServ domain. However, the dynamic allocation of resources within the domain allows to ensure the per-flow QoS guarantees and achieve better performance. At the moment, several signaling solutions for DiffServ framework are available. Thus, it is crucial to analyse these solutions and interconnections between them. In particular, the RSVP, aggregated RSVP, GIST, COPS, and SIP protocols will be considered. The simulation comprises several scenarios that present that the dynamic allocation of resource within…
Condition Assessment of Norwegian Bridge Elements Using Existing Damage Records
2020
The Norwegian Public Roads Administration (NPRA) has recorded bridge element damages in a database for all the bridges it manages since the 1990s. This paper presents a comparison of three methods to establish element condition based on damage records. The methods consist in a non-parametric procedure based on the worst damage registered in the element, linear regression considering also bridge and road characteristics data and classification through an artificial neural network. The methods are assessed using a set of 159 bridges inspected in 2016. The results show that diagnostics of bridge element condition can reach high accuracy by using an artificial neural network classifier and taki…
Trust management in tactical coalition software defined networks
2018
This paper reports from ongoing efforts related to trust management in tactical Software Defined Networks (SDN) when used with mobile nodes in a coalition operation. We analyze the problem space and suggests a set of security and contructional requirements, as well as an analysis on how existing technology may contribute to a solution. The proposed architecture serves as a guide for current and future experimentation on trust management and protection in SDN. The paper also reports from experimental investigations into the utility of these technology elements for the present purpose.
Development of a Design Procedure for Bending Operations
1999
Springback can be considered as one of the most important shape defect in sheet stamping. Such effect results relevant even when simple bending operations are taken into account. In the paper the authors present a design procedure able to provide the proper value of the punch stroke to be applied in order to compensate for elastic springback. In particular two approaches have been followed: firstly an inverse design technique has been utilized in order to find out the response function governing the investigated phenomenon; furthermore neural network techniques have been applied in order to represent the logical link between the input data and the aimed output, i.e. the proper punch stroke …
Unknown order process emulation
2002
Approaches the emulation problem using feedforward neural networks of single input single output (SISO) processes, applying a backpropagation method with a higher convergence rate. In this kind of application, difficult problems appear when the system's order is a priori unknown. A search through the SISO processes space is proposed, aiming to find a favorable neural emulator over the training examples set.
Identification of parameters of dynamic Preisach model by neural networks
2008
In this paper, an approach that allows to identify the parameters of dynamic Preisach model is presented. The fundamental idea of this method is to identify the parameters of a material by using a neural network trained by a collection of hysteresis curves, whose Preisach model is known. After a brief description of dynamic Preisach Model, the neural network that has been used is introduced. The construction of the training data set is illustrated. Finally, the effectiveness of the method is tested on both numerical as well as experimental data.
The simulation and analysis of the revenue critierion based adaptive WFQ
2003
This paper presents the simulation and analysis of the adaptive resource allocation model, which was proposed and theoretically considered in our previous works. It relies upon the Weighted Fair Queueing (WFQ) service policy and uses the revenue criterion to adjust weights. The purpose of the proposed model is to maximize a provider's revenue and, at the same time, ensure the required Quality-of-Service (QoS) for end-users. Our previous works provided the theoretical evaluation of the proposed model and considered the single-node case only. This paper presents more realistic network scenario, which includes a set of clients and several intermediate switching nodes with the proposed model. T…