Delay-Tolerant ICN and Its Application to LoRa

Connecting long-range wireless networks to the Internet imposes challenges due to vastly longer round-trip-times (RTTs). In this paper, we present an ICN protocol framework that enables robust and efficient delay-tolerant communication to edge networks. Our approach provides ICN-idiomatic communication between networks with vastly different RTTs. We applied this framework to LoRa, enabling end-to-end consumer-to-LoRa-producer interaction over an ICN-Internet and asynchronous data production in the LoRa edge. Instead of using LoRaWAN, we implemented an IEEE 802.15.4e DSME MAC layer on top of the LoRa PHY and ICN protocol mechanisms in RIOT OS. Executed on off-the-shelf IoT hardware, we provide a comparative evaluation for basic NDN-style ICN [60], RICE [31]-like pulling, and reflexive forwarding [46]. This is the first practical evaluation of ICN over LoRa using a reliable MAC. Our results show that periodic polling in NDN works inefficiently when facing long and differing RTTs. RICE reduces polling overhead and exploits gateway knowledge, without violating ICN principles. Reflexive forwarding reflects sporadic data generation naturally. Combined with a local data push, it operates efficiently and enables lifetimes of >1 year for battery powered LoRa-ICN nodes.Comment: 12 pages, 7 figures, 2 table

Polling-Based Downlink Communication Protocol for LoRaWAN using Traffic Indication

학위논문 (석사)-- 서울대학교 대학원 : 공과대학 컴퓨터공학부, 2019. 2. 김종권.LPWAN (Low Power Wide Area Network) technologies such as LoRa and SigFox are emerging as a technology of choice for the Internet of Things (IoT) applications where tens of thousands of untethered devices are deployed over a wide area. In such operating environments, energy conservation is one of the most crucial concerns and network protocols adopt various power saving schemes to lengthen device lifetimes. For example, to avoid idle listening, LoRaWAN restricts downlink communications. However, the confined design philosophy impedes the deployment of IoT applications that require asynchronous downlink communications. In this thesis, we design and implement an energy efficient downlink communication mechanism, named TRILO, for LoRaWAN. We aim to make TRILO be energy efficient while obeying an unavoidable trade-off that balances between latency and energy consumption. TRILO adopts a beacon mechanism that periodically alerts end-devices which have pending downlink frames. We implement the proposed protocol on top of commercially available LoRaWAN components and confirm that the protocol operates properly in real-world experiments. Experimental results show that TRILO successfully transmits downlink frames without losses while uplink traffic suffers from a slight increase in latency because uplink transmissions should halt during beacons and downlink transmissions. Computer simulation results also show that the proposed scheme is more energy efficient than the legacy LoRaWAN downlink protocol.전력 공급이 제한적인 수 만개의 디바이스들을 이용하여 넓은 지역을 바탕으로 운영되는 사물인터넷 시스템을 구축하는 데에 있어서 LoRa, SigFox와 같은 저전력 광역 네트워크 기술(LPWA)이 주목받고 있다. 이러한 시스템 환경에서 에너지 절약은 중요한 관심사 중 하나이며 네트워크 프로토콜들은 다양한 절전 방식을 채택하여 디바이스의 수명을 보장하려 하고 있다. 예를 들어, 불필요한 대기 청취로 인한 에너지 손실을 방지하기 위해서 LoRaWAN은 다운링크 통신을 제한하고 있는데, 이러한 설계 철학은 비동기적인 다운링크 통신을 필요로 하는 IoT 애플리케이션의 요구 사항을 충족시키지 못하는 문제점을 가지고 있다. 따라서 본 논문에서는 LoRaWAN에서 다운링크를 효과적으로 컨트롤할 수 있도록 TRILO라는 에너지 효율적인 다운링크 통신 메커니즘을 설계하고 구현하였다. TRILO는 다운링크 프레임이 팬딩되어 있는 엔드 디바이스들의 리스트 정보를 주기적으로 네트워크에 알리는 비콘 메커니즘을 채택하였고, 서버와 디바이스들이 각각 정해진 순서에 따라 다운링크 전송 및 수신을 스케줄링하도록 하였다. 설계한 프로토콜이 제대로 동작하는지 검증하기 위해서 기존 LoRaWAN의 구성 요소 위에 제안된 프로토콜을 구현한 후 실제 테스트 베드를 구축하여서 실험을 진행하였다. 실험 결과에 따르면 TRILO는 기존 프로토콜의 업링크 통신 성능을 저해하지 않으면서도 추가적인 다운링크 프레임을 손실 없이 성공적으로 전송 및 수신하였고, 컴퓨터 시뮬레이션 결과 또한 제안된 기법이 기존의 LoRaWAN 다운링크 프로토콜보다 더 에너지 효율적으로 동작하는 것을 보여주었다.ABSTRACT ........................................................................................................... ⅰ CONTENTS ........................................................................................................... ⅲ LIST OF FIGURES ............................................................................................ ⅳ LIST OF TABLES .............................................................................................. ⅵ CHAPTER Ⅰ: Introduction ................................................................................ 1 CHAPTER Ⅱ: Related Work ............................................................................. 8 CHAPTER Ⅲ: A Primer on LoRa and LoRaWAN .................................. 11 CHAPTER Ⅳ: Downlink Communications Scheme .................................. 17 4.1 Comparison of Two Polling Schemes ..................................... 19 4.2 Proposed Downlink Communications Scheme ....................... 26 CHAPTER Ⅴ: Implementation ........................................................................ 28 CHAPTER Ⅵ: Evaluation ................................................................................. 31 6.1 Experimental Results .................................................................... 32 6.2 Simulation Results ......................................................................... 37 CHAPTER Ⅶ: Discussion ................................................................................. 42 CHAPTER Ⅷ: Conclusion ................................................................................. 45 BIBLIOGRAPHY ................................................................................................... 47 초록 ........................................................................................................................... 51Maste

Relaying in the Internet of Things (IoT): A Survey

The deployment of relays between Internet of Things (IoT) end devices and gateways can improve link quality. In cellular-based IoT, relays have the potential to reduce base station overload. The energy expended in single-hop long-range communication can be reduced if relays listen to transmissions of end devices and forward these observations to gateways. However, incorporating relays into IoT networks faces some challenges. IoT end devices are designed primarily for uplink communication of small-sized observations toward the network; hence, opportunistically using end devices as relays needs a redesign of both the medium access control (MAC) layer protocol of such end devices and possible addition of new communication interfaces. Additionally, the wake-up time of IoT end devices needs to be synchronized with that of the relays. For cellular-based IoT, the possibility of using infrastructure relays exists, and noncellular IoT networks can leverage the presence of mobile devices for relaying, for example, in remote healthcare. However, the latter presents problems of incentivizing relay participation and managing the mobility of relays. Furthermore, although relays can increase the lifetime of IoT networks, deploying relays implies the need for additional batteries to power them. This can erode the energy efficiency gain that relays offer. Therefore, designing relay-assisted IoT networks that provide acceptable trade-offs is key, and this goes beyond adding an extra transmit RF chain to a relay-enabled IoT end device. There has been increasing research interest in IoT relaying, as demonstrated in the available literature. Works that consider these issues are surveyed in this paper to provide insight into the state of the art, provide design insights for network designers and motivate future research directions

GNSS-free outdoor localization techniques for resource-constrained IoT architectures : a literature review

Large-scale deployments of the Internet of Things (IoT) are adopted for performance improvement and cost reduction in several application domains. The four main IoT application domains covered throughout this article are smart cities, smart transportation, smart healthcare, and smart manufacturing. To increase IoT applicability, data generated by the IoT devices need to be time-stamped and spatially contextualized. LPWANs have become an attractive solution for outdoor localization and received significant attention from the research community due to low-power, low-cost, and long-range communication. In addition, its signals can be used for communication and localization simultaneously. There are different proposed localization methods to obtain the IoT relative location. Each category of these proposed methods has pros and cons that make them useful for specific IoT systems. Nevertheless, there are some limitations in proposed localization methods that need to be eliminated to meet the IoT ecosystem needs completely. This has motivated this work and provided the following contributions: (1) definition of the main requirements and limitations of outdoor localization techniques for the IoT ecosystem, (2) description of the most relevant GNSS-free outdoor localization methods with a focus on LPWAN technologies, (3) survey the most relevant methods used within the IoT ecosystem for improving GNSS-free localization accuracy, and (4) discussion covering the open challenges and future directions within the field. Some of the important open issues that have different requirements in different IoT systems include energy consumption, security and privacy, accuracy, and scalability. This paper provides an overview of research works that have been published between 2018 to July 2021 and made available through the Google Scholar database.5311-8814-F0ED | Sara Maria da Cruz Maia de Oliveira PaivaN/