• 한국인터넷방송통신학회논문지
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• 제19권2호
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• pp.91-96
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• 2019

일반적인 무선 센서 네트워크는 연결이 안정적이지 않고 외부 간섭에 민감하며 토폴로지가 유동적이므로 상황에 맞는 효율적인 전송 경로 설정이 중요하다. IETF (Internet Engineering Task Force)의 RPL(IPv6 Routing Protocol for Low-power Lossy Networks) 표준 라우팅 프로토콜은 다양한 환경 변화에 유연하게 대응하기 어려우며 네트워크 토폴로지의 불균형으로 인한 패킷 손실 문제가 상존한다. 다중경로로 여러 부모 노드를 통해 패킷을 전송할 경우 이러한 문제를 부분적으로 해결할 수 있지만 경우에 따라 필요 이상의 timeslot 할당으로 지연시간 증가를 초래할 수 있다. 본 논문에서는 상황에 따라 적절하게 다중경로를 사용하는 적응형 다중경로 RPL 알고리즘을 제안하고, 시뮬레이션을 통해 이의 효율성이 기존 RPL이나 다중경로 RPL에 비해 높음을 보였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권4호
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• pp.2002-2019
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• 2017

RPL routing protocol for low-power and lossy networks is an Internet Engineering Task Force (IETF) recommended IPv6 based protocol for routing over Low power Lossy Networks (LLNs). RPL is proposed for networks with characteristics like small packet size, low bandwidth, low data rate, lossy wireless links and low power. RPL is a proactive routing protocol that creates a Directed Acyclic Graph (DAG) of the network topology. RPL is increasingly used for Internet of Things (IoT) which comprises of heterogeneous networks and applications. RPL proposes a single path routing strategy. The forwarding technique of RPL does not support multiple paths between source and destination. Multipath routing is an important strategy used in both sensor and ad-hoc network for performance enhancement. Multipath routing is also used to achieve multi-fold objectives including higher reliability, increase in throughput, fault tolerance, congestion mitigation and hole avoidance. In this paper, M-RPL (Multi-path extension of RPL) is proposed, which aims to provide temporary multiple paths during congestion over a single routing path. Congestion is primarily detected using buffer size and packet delivery ratio at forwarding nodes. Congestion is mitigated by creating partially disjoint multiple paths and by avoiding forwarding of packets through the congested node. Detailed simulation analysis of M-RPL against RPL in both grid and random topologies shows that M-RPL successfully mitigates congestion and it enhances overall network throughput.