• Journal of Korea Society of Digital Industry and Information Management
• /
• v.15 no.1
• /
• pp.21-28
• /
• 2019

Internet of Things(IoT) is a technology or environment that collects data by attaching sensors to objects and transmits the collected information to each other through wired / wireless communication in real time. It is expected that when the Internet of objects is activated, many objects can identify and recognize each other by themselves and provide various services to facilitate our lives through mutual information exchange. In addition, the internet market for things is growing rapidly each year, and various IT technologies are expected to converge. In the Internet environment of objects, data exchange technology between object devices, that is, message protocol, is classified as one of important technologies. In this paper, we examine various lightweight message protocols suitable for the Internet environment of objects, and compare the reliability of the CoAP protocol structure with the MQTT protocol for a limited environment. Finally, we confirm the reliability of TCP / TLS and WebSockets-based CoAP transmission protocol of IETF's CoRE WG that can use various transport layers other than UDP in Internet environment including cloud infrastructure.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2017.05a
• /
• pp.586-589
• /
• 2017

The vibration monitoring system using the sensor network is used in various fields. However, in case of the vibration of the existing products, the size of the monitoring system is increased due to the separation of the sensor data collection function and the communication function. In this paper, we design and implement a lightweight vibration monitoring system using the MQTT protocol, which is oneM2M device standard protocol for the Arduino and Ethernet modules, to monitor frequent earthquakes and vibrations in narrow places.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.22 no.6
• /
• pp.7-12
• /
• 2022

This paper introduces the implementation of the AWS IoT service and MQTT based smart home system. The smart home system implemented in this study can monitor temperature and humidity, and can manually adjust the air conditioner heating, and can check the visitors with the camera and remotely control the door lock. The implemented smart home system controls door locks, heating and air conditioners using Arduino, and manages the collected data and control information using the AWS IoT service. In this study, the Android app has been developed to allow users to control IoT devices remotely, and the MQTT protocol was used for data communication and control between the app and the AWS IoT server and Arduino. The implemented smart home system has been implemented based on AWS IoT service, which has scalability to add sensors and devices.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2016.04a
• /
• pp.297-299
• /
• 2016

기술의 발달과 융합으로 사물인터넷(Internet of Things; IoT)의 시대가 열렸다. 빅 데이터와 센서의 발달로 인해 정보는 전과 달리 더욱 사용자와 밀접해졌고 다양해졌으며 양 또한 많아졌다. 이와 더불어 IoT 환경은 다양한 기술들이 융합된 구조로 기존 기술들이 가지고 있는 보안 취약점뿐만 아니라 보다 복잡한 보안 문제점들이 발생할 수 있다. 본 논문에서는 IoT 환경에서 서비스나 IoT 기기들이 갖춰야할 보안 요구사항들을 확장성(scalability), 상호운용성(interoperability), 최소 자원 필요성(minimum resource necessity)으로 분류 하고 정의하였으며, IoT 서비스를 제공하기 위해 사용하는 대표적 프로토콜인 MQTT(Message Queue Telemetry Transfer)와 CoAP(Constrained Application Protocol)에 초점을 맞춰 각각의 표준 문서에서 권고하고 있는 보안 기술에 대해 살펴본다. 또한 그런 기술들에 있어서 발생 가능한 보안 취약점들을 분석하고 이를 해결하기 위한 방법을 제시한다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2014.11a
• /
• pp.73-76
• /
• 2014

현재 네트워크 시스템은 유선에서 무선으로 발전하면서 많은 업무가 모바일 기반의 업무로 변화되고 있다. 그 중 대표적인 것이 모바일 오피스 시스템으로 중요 구성요소 중 하나인 커뮤니케이션은 구성원간의 단문 메시지 서비스(SMS)이다. 그러나 최근 무선 환경의 발전으로 단문 메시지 전송 방식이 SMS에서 모바일 메신저로 변화하고 있으나 그에 대처하지 못한 시스템들이 있다. 이에 본 논문에서는 모바일 오피스 시스템에서 사용되고 있는 SMS를 대체하여 MQTT(Message Queuing Telemetry Transport) 프로토콜을 이용한 협업 메신저 시스템을 설계 및 구현한다.

• Journal of Korea Multimedia Society
• /
• v.23 no.3
• /
• pp.421-429
• /
• 2020

Recently, with the development of IoT technology and the increase of energy consumption, interest in energy saving and energy efficiency improvement is rapidly increasing. In particular, in the case of a device connected to a power plug with the power shutoff, a problem with standby power has been raised. Thus technology development through a low power method such as Zigbee is in progress. However, Zigbee, which is generally used, has a problem that a separate gateway is required because it is not an IP-based technology, and there is a problem that it is not suitable for a traditional computer network to which a variety of devices are connected. Therefore, in this paper, we designed and implemented a standby power saving system using MQTT, an IoT standard protocol, in Z-Wave environment. In order to evaluate the implemented standby power saving system, the same environment as the existing Zigbee-based standby power saving system was compared and evaluated.

• Journal of Korea Multimedia Society
• /
• v.17 no.12
• /
• pp.1461-1472
• /
• 2014

Recently, smart devices has been spreaded and the definition of RFID/USN(Radio Frequency Identification/Ubiquitous Sensor Network) technology has also extended. So, originally, human is an agent of communications but now, 'the things' are also an agent of communication. That is, Internet of Things(IoT). IoT is very big IT infra technology that is based on wire-wireless network technologies such as Bluetooth and Wi-Fi. However, in reality, IoT service that can provide various meaning and integrate smoothly is not appear yet. To solve these problems of IoT, we implemented Publish/Subscribe system, which operate in Zigbee based wireless sensor network by using MQTT-SN protocol. Moreover, this system can operate with combining MQTT system that is already existed in external Internet network so, extensibility and flexibility aspect is excellent. We show that possibility of IoT services that is combined between different heterogeneous network through the MQTT-SN.

• Journal of Platform Technology
• /
• v.9 no.4
• /
• pp.79-89
• /
• 2021

In this paper, the fine dust (PM10) and ultrafine dust (PM2.5) measurement platforms are designed to be mobile and fixed using oneM2M, the international standard for IoT. The fine dust measurement platform is composed and designed with a fine dust measurement device, agent, oneM2M platform, oneM2M IPE, and monitoring system. The main difference between mobile and fixed is that the mobile uses the MQTT protocol for interconnection between devices and services without blind spots based on LTE connection, and the fixed uses the LoRaWAN protocol with low power and wide communication range. Not only fine dust, but also temperature, humidity, atmospheric pressure, volatile organic compounds (VOC), carbon monoxide (CO), sulfur dioxide (SO2), nitrogen dioxide (NO2), and noise data related to daily life were collected. The collected sensor values were managed using the common API provided by oneM2M through the agent and oneM2M IPE, and it was designed into four resource types: AE and container. Six functions of operability, flexibility, convenience, safety, reusability, and scalability were analyzed through the fine dust measurement platform design.

• Journal of Internet of Things and Convergence
• /
• v.10 no.2
• /
• pp.131-135
• /
• 2024

In the MQTT protocol, if the retained flag of a message published by a publisher is set, the message is stored in the broker as a retained message. When a new subscriber performs a subscribe, the broker immediately sends the retained message. This allows the new subscriber to perform updates on the current state via the retained message without waiting for new messages from the publisher. However, sending retained messages can become a traffic overhead if new messages are frequently published by the publisher. This situation could be considered an overhead when new subscribers frequently subscribe. Therefore, in this paper, we propose a retained message delivery scheme by considering the characteristics of the published messages. We model the delivery and waiting actions to new subscribers from the perspective of the broker using reinforcement learning, and determine the optimal policy through Q learning algorithm. Through performance analysis, we confirm that the proposed method shows improved performance compared to existing methods.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.10
• /
• pp.1895-1902
• /
• 2016

People and goods through the recent smart device, IoT to things and things are connected, it has emerged as the driving force of a new economic growth in the future. While conducting research of this international standardization organization in the IoT-based protocol, to the institutions and companies that belong to the standards bodies interests are different from each other, protocols have been developed also, different order, heterogeneous device interoperability has emerged is a problem that the lowering of. Therefore, in this paper, to investigate the structure of the MQTT and CoAP that are commonly used and trying to figure out the trend of low power consumption, a lightweight protocol that is suitable for IoT environment, process and standardization trends of evolution, features, analysis and on, to derive the advantages and disadvantages, and comparative analysis, it presented a development scheme for each protocol.