• 한국항해항만학회지
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• 제38권4호
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• pp.343-348
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• 2014

새로운 해상통신망 모델로 자율망 모델과 광대역 무선접속기술의 다양성과 혼재성을 활용하고 경로상의 홉 단위로 최적노드와 캐리어를 선택하는 경로배정방식(MCS-NLTC)을 새롭게 제안한다. 여기서는 일반적인 홉 수가 아니라 목적지 선박과의 거리(위치정보)가 기본적인 기준이 되고 캐리어의 전송특성의 정규값을 가중치로 삼아 최적경로를 탐색하는 방식이다. 위치정보가 기본적으로 고려되기 때문에 탐색 수렴성이 개선되어 탐색시간이 크게 단축되고 경로의 최적성도 향상되었다. 기존 전송특성의 절대값을 상호 비교하는 최다승방식(OMH-MW)과 전송특성의 정규값만을 고려하는 방식(MCS-NTC)과 성능을 비교하여 이를 확인하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권12호
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• pp.4411-4431
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• 2014

Mobile ad hoc networks (MANETs) have recently gained increased interest due to the widespread use of smart mobile devices. Group communication applications, serving for better cooperation between subsets of business members, become more significant in the context of MANETs. Multicast routing mechanisms are very useful communication techniques for such group-oriented applications. This paper deals with multicast routing problems in terms of stability and scalability, using the concept of stable core. We propose LMRSC (Lightweight Multicast Routing Based on Stable Core), a lightweight multicast routing technique for MANETs, in order to avoid periodic flooding of the source messages throughout the network, and to increase the duration of multicast routes. LMRSC establishes and maintains mesh architecture for each multicast group member by dividing the network into several zones, where each zone elects the most stable node as its core. Node residual energy and node velocity are used to calculate the node stability factor. The proposed algorithm is simulated by using NS-2 simulation, and is compared with other multicast routing mechanisms: ODMRP and PUMA. Packet delivery ratio, multicast route lifetime, and control packet overhead are used as performance metrics. These metrics are measured by gradual increase of the node mobility, the number of sources, the group size and the number of groups. The simulation performance results indicate that the proposed algorithm outperforms other mechanisms in terms of routes stability and network density.