Junghwa Shin

Design of Dual Network Topology and Redundant Transmitting Protocol for High Survivability of Ship Area Network (SAN)

ABSTRACT In the shipbuilding industry, due to the global trends where the number of IT (Information Technology) devices of a smart ship have been increased rapidly, the need to develop a new shipboard backbone network has recently emerged for integrating and managing the IT devices of a smart ship efficiently. A shipboard backbone network requires high survivability because it is constructed in automatic and unmanned smart ships where a failure of the backbone network can cause critical problems. The purpose of this paper thus is to study SAN (Ship Area Network) as a efficient shipboard backbone network, considering particularity of shipboard environment and requirement of high survivability. In order to do so, we designed a dual network topology that all network nodes, including the IT devices installed in a smart ship, are connected each other through dual paths, and reuding tht IT devices pnstalles supporices network survivability as well as t Iffic efficiency for the dual network topology. And then, we verified the performance of the suggested SAN by theoretical and practical analysis including the graph theory, the probability theory, implemental specifications, and computer simulations.Keywords:Ship Area Network, Smart Ship, Network Survivability

TrustRRM: An Improved Reputation Management Scheme Handling Dishonest Feedback in Peer-to-Peer Networks

Because the P2P networks have no trusted third parties that can manage the behaviors of peers and control the malicious peers, peers can give harm to correct peers by providing inauthentic resources for the benefit of themselves in resource sharing service. Under this situation, peers can refer the reputation that reflects peers past behaviors to download the authentic resources from reliable peers. In the utilization of reputation, sometimes peers intentionally can give a dishonest feedback to fake the reputation of other peers. Therefore, we propose a new reputation management scheme, called TrustRRM (Trusty Reputation Management for Resource Sharing Service) that can manage the dishonest feedback of peers and improve the reliability of resource sharing service. We compare the effectiveness of TrustRRM scheme, and existing reputation management schemes using NS-2 Simulator. A case study on practical experiments and simulations show that the TrustRRM scheme yields better performance in terms of download ratio of inauthentic resources, success ratio of download request, and in/out-degrees of malicious and good peer.

An Improved Reputation Management Scheme for Reliable Resource Sharing

In P2P networks, peers generally interact with unknown or unfamiliar peers without trusted third parties that can manage the behaviors of peers or control the malicious peers. They can give harm to correct peers by providing inauthentic resources for the benefit of themselves in resource sharing. Under this situation, peers can refer the reputation that reflects peers past behaviors to download the authentic resources from reliable peers. P2P networks utilize mainly a reputation to provide shared resources and peers with trustworthiness, many schemes available in literature have been proposed to manage of reputation. In this paper, we propose a new reputation management scheme to improve the trustworthiness of peers and shared resources, and restrain the participation of free-riders. In the proposed scheme, we update the good and bad reputation of peer according to the rating that peer received from the t(n) and t(n+1) transaction. And, we can lead to the increment or decrement of reputation by reflecting the ratio of shared resources when calculate the good and bad reputation of peer. The reputation makes an impact on the calculation of trust value of peers. Also, we can restrain the participation of free-riders who does not contribute resources and malicious peers by exploiting this value. Therefore, the proposed scheme can improve the performance of resource sharing system.

CLARM routing: cross layer adhoc-routing based on reputation management in wireless multi-hop networks

This paper presents a framework of wireless multi-hop networks exploiting an ad hoc routing protocol working on the layer 2.5, called CLARM (Cross Layer Adhoc-routing based on Reputation Management) routing protocol. The framework of CLARM routing protocol incorporates following three things: a new concept of wireless multi-hop network architecture, a new 2.5-layer routing technique with a reputation management scheme, high throughput network performance based on cross-layer approache between MAC (Medium Access Control) and CLARM layers. We compare the performance of the CLARM routing protocol with previous routing algorithms, DSR (Dynamic Source Routing) and AODV (Ad hoc On demand Distance Vector), previous reputation management scheme CORE (COllaborative REputation) and CONFIDANT (COoperation Of Nodes Fairness In Dynamic Ad Hoc NeTworks). A case study on practical experiments and simulations shows that the CLARM routing protocol yields better performance in terms of low rate of packet loss and high throughput network performance.

REAL Routing: REputation Based Approach on 2.5-Layer Routing for Reliable Packet Delivery in Wireless Multi-Hop Networks

This paper presents a framework of wireless multi-hop networks exploiting an ad hoc routing protocol working on the layer 2.5, called REAL (reputation based approach on 2.5-Layer) routing protocol. The framework of REAL routing protocol incorporates following three things: a new concept of wireless multi-hop network architecture, a new 2.5-layer routing technique with a reputation management scheme, and high throughput network performance based on cross-layer approaches between MAC (medium access control) and REAL layers. We compare the performance of the REAL routing protocol with previous routing algorithms, DSR (dynamic source routing) and AODV (ad hoc on demand distance vector). A case study on practical experiments and simulations shows that the REAL routing protocol yields better performance in terms of low rate of packet loss, fast packet delivery time, and high throughput network performance.