LOAMY: a Cloud-based Middleware for CoAP-based IoT Service Discovery

Service discovery is one of the key requirements to realize the vision of the Internet of Things (IoT). Constrained application protocol (CoAP) is a well-accepted model that utilizes both centralized and distributed service discovery methods for lightweight and constrained IoT networks. Since CoAP is in its early stage of adoption for the IoT networks, it is important to select an efficient method for the service discovery requirement. In this paper, we implement both centralized and distributed models of the CoAP based service discovery techniques. We have used Contiki OS and Cooja simulator to build the experimental setup for our prototype systems. Our detailed empirical analysis finds the gaps in general CoAP based service discovery techniques to recommend further improvement scopes.

Reliable Internet of Things (IoT) service discovery is a significant task in intelligent service-oriented IoT systems. Collaborative filtering (CF) turns out to be an effective solution to IoT service discovery. However, the traditional CF framework is facing the following challenges: inefficiency in learning the high-order interactions between users and IoT services and ineffectively making use of geographical location information. Moreover, deploying a CF framework in real-world distributed IoT systems poses another significant challenge in terms of reliability assurance and privacy protection. For bridging this gap, we propose an innovative integrated collaborative filtering framework (ICF) with incorporating the location-aware quality of IoT services into a heterogeneous graph embedding model. Meanwhile, a Geohash-based privacy-preservation mechanism is introduced to encoding the location information into a short string for protecting the sensitive location information. The proposed ICF framework is an integrated architecture combining advanced graph embedding learning and heterogeneous side information. And a joint objective optimization function is designed in the graph embedding learning to qualify automatic IoT service features. In this way, the hidden user-service interaction information and location-aware quality semantic features can be explored in an effective and reliable way. Furthermore, the learned location-aware quality embedding vector is incorporated to discover the reliable services among all IoT services with the mini-batch online clustering-based CF algorithm. The experimental findings illustrate the significant efficacy and reliability of our proposed ICF framework in large scale IoT service discovery scenarios.

Purpose – The purpose of this paper is to study lightweight security scheme for Internet of Things (IoT) applications using Constrained Application Protocol (CoAP). Resource-constrained characteristics of IoT systems have ushered in compelling requirements for lightweight application protocol and security suites. CoAP has already been established as the candidate protocol for IoT systems. However, low overhead security scheme for CoAP is still an open problem. Existing security solutions like Datagram Transport Layer Security (DTLS) is not suitable, particularly due to its expensive handshaking, public key infrastructure (PKI)-based authentication and lengthy ciphersuite agreement process. Design/methodology/approach – This paper proposes a lightweight security scheme in CoAP using Advanced Encryption Standard (AES) 128 symmetric key algorithm. The paper presents an object security (payload embedded)-based robust authentication mechanism with integrated key management. The paper introduces few unique modifications to CoAP header to optimize security operation and minimize communication cost. Findings – It is resilient to number of security attacks like replay attack, meet-in-the-middle attack and secure under chosen plaintext attack. This scheme is generic in nature, applicable for gamut of IoT applications. The paper proves efficacy of our proposed scheme for vehicle tracking application in emulated laboratory setup. Specifically, it compares with DTLS-enabled CoAP to establish the lightweight feature of our proposed solution. Research limitations/implications – This paper mainly focuses on implementing in-vehicle tracking systems as an IoT application and used CoAP as the application protocol. Practical implications – Such a lightweight security scheme would provide immense benefit in IoT systems so that resource constraint-sensing devices and nodes can be made secure. This would impact IoT eco systems to a large extent. Originality/value – Such kind of security suite that provides both robustness and lightweight feature is hitherto not known to the authors, particularly in CoAP for IoT applications.

The Internet of Things (IoT) is a framework of interconnected computing devices mechanical and digital machines, internationally identifiable physical objects (or things) or people that are have unique identity and the ability to transfer data over a network without human-to-human or human-to-computer interaction., their combination with the Internet, and their representation in the digital world. The accessibility and availability of cheap components of IoT devices enables a extensive range of applications and provide smart environments. These devices perform actuating and sensing tasks and identified through unique addresses. The IoT devices are connected to the Internet and expected to use the Constrained Application Protocol (CoAP) at the application layer as a main web transfer protocol. Message Queuing Telemetry Transport (MQTT) does not enforce the use of a particular security approach for its applications, but instead leaves that to the application designer. Therefore, IoT solutions can be based on application context and specific security requirements. MQTT is a Client Server publish/subscribe messaging transport protocol. It is lightweight, open, uncomplicated, and designed to make implementation more easier. These characteristics of MQTT make it perfect for use in most of the situations, including communication in Machine to Machine (M2M) and Internet of Things (IoT). In IOT there is major use of Wireless Sensor Networks (WSN) which connects virtual world to physical world. In this paper focus is given to application layer of IOT. In application layer two important protocols are MQTT and CoAP. Security mechanism is proposed in the paper for these protocols.

Recently, IETF (Internet Engineering Task Force) presented CoAP (Constrained Application Protocol) for the communication between sensor and actuator nodes in a constrained environment such as small amount of memory and low power. IETF CoAP protocol can convert easily, and can use to monitor or control infrastructure utilities through low-power sensor and actuator networks in IoT (Internet of Things) and M2M (Machine-to-Machine) environment. IETF CoAP protocol provides the special requirements of this constrained environment, especially considering energy, automation, and other IoT applications. In this paper, we design and implement a node registration and discovering based CoAP in IoT environment. The node is a CoAP node which is designed for working in constrained environment. For node registration in IoT, we used CoRE RD (Resource Directory) functionalities to register CoAP node’s information which works in IoT environment.

The Internet of Medical Things (IoMT) is a collection of medical equipment and software that can help patients get better care. The purpose of this study is to improve the security of data collected through remote health monitoring of patients utilizing Constrained Application Protocol (CoAP). Asymmetric cryptography techniques may be used to assure the security of such sensor networks. For communication between different IoMT devices and a remote server, the safe CoAP is compatible with the Datagram Transport Layer Security (DTLS) protocol for creating a secure session using existing algorithms such as Lightweight Establishment of Secure Session. The DTLS layer of CoAP, in contrast, has shortcomings in key control, session establishment, and multicast message exchange. As a consequence, for IoMT communication, the creation of an efficient protocol for safe CoAP session establishment is needed. Thus, to solve the existing problems related to key management and multicast security in CoAP, we have proposed an efficient and secure communication technique to establish a secure session key between IoMT devices and distant servers using lightweight Energy-Efficient and Secure CoAP Elliptic Curve Cryptography (E2SCEC2). The advantage of using E2SCEC2 over other identification methods such as Rivest-Shamir-Adleman (RSA) is its compact key size, which allows it to use a smaller key size. This article also compares these algorithms on parameters such as time spent generating keys, signature generation, and verification of E2SCEC2 and RSA algorithms, as well as energy consumption and radio duty cycle, to see if they are compatible in constrained environments.

The Internet of Things (IoT) is playing a key role in consumer and business environments. Due to the sensitivity of the information IoT devices collect and share, and the potential impact a data breach can have in people’s lives, securing communication and access to data in IoT has become a critical feature. Multiple application layer protocols are used nowadays in IoT, with the Constrained Application Protocol (CoAP) and the Message Queue Telemetry Transport (MQTT) being two of the most widely popular. In this paper, we propose a solution to increase the security of both CoAP and MQTT based on the distributed Usage Control (UCON) framework. The inclusion of UCON provides dynamic access control to the data shared using these protocols. This occurs by monitoring mutable attributes related to the local protocol nodes and also by sharing data values between remote nodes via the distributed instances of UCON. We present the architecture and the workflow of our approach together with a real implementation for performance evaluation purposes.

Internet of Things (IoT) is a massive network based on tiny devices connected internally and to the internet. Each connected device is uniquely identified in this network through a dedicated IP address and can share the information with other devices. In contrast to its alternatives, IoT consumes less power and resources; however, this makes its devices more vulnerable to different types of attacks as they cannot execute heavy security protocols. Moreover, traditionally used heavy protocols for web-based communication, such as the Hyper Text Transport Protocol (HTTP) are quite costly to be executed on IoT devices, and thus specially designed lightweight protocols, such as the Constrained Application Protocol (CoAP) are employed for this purpose. However, while the CoAP remains widely-used, it is also susceptible to attacks, such as the Distributed Denial-of-Service (DDoS) attack, which aims to overwhelm the resources of the target and make them unavailable to legitimate users. While protocols, such as the Datagram Transport Layer Security (DTLS) and Lightweight and the Secure Protocol for Wireless Sensor Network (LSPWSN) can help in securing CoAP against DDoS attacks, they also have their limitations. DTLS is not designed for constrained devices and is considered as a heavy protocol. LSPWSN, on the other hand, operates on the network layer, in contrast to CoAP which operates on the application layer. This paper presents a machine learning model, using the CIDAD dataset (created on 11 July 2022), that can detect the DDoS attacks against CoAP with an accuracy of 98%.

Constrained Application Protocol (CoAP) is a communication protocol at application layer in the Internet of things (IoT). It employs NSTART parameter to maintain outstanding parallel connections toward individual destinations for data transfer. In the existing implementation of CoAP, the value for NSTART is defined statically. Where the higher values of this parameter up to a threshold give better throughput in moderate traffic, the lower values for the same control the congestion in overload situations. In overload situations, higher values of NSTART result in increased overhead and thereby perform poorly in terms of throughput. The static nature of the parameter and its relevant performance issues demand to manage NSTART dynamically in CoAP. In this work, we propose an algorithm to adjust the value of NSTART dynamically based on the congestion in the network. The proposed approach is an attempt to make the client free from managing NSTART dynamically. For the proof of concept, we implement and run simulations on Cooja mote at IoT/FIT-Lab testbed and Californium CoAP client. The results show 15% improvement in throughput, 15% reduction in average exchange duration, and 48% reduction in average number of retries (average taken of three scenarios) by proposed approach in comparison with the best case of CoCoA (NSTART = 4).

For Web-based applications in Internet of Things (IoT) environment, the IETF CoRE Working Group developed the Constrained Application Protocol (CoAP). A limitation of CoAP is that it does not address a mobility management for CoAP sensor nodes, which may move between different IP domains of a wireless sensor network. In this paper, we propose the CoAP-based Mobility Management Protocol (CoMP), which can provide mobility management for mobile CoAP sensor nodes. CoMP keeps track of the current IP addresses of mobile sensor and enables sensing data to be reliably delivered to the Web clients, using both HTTP and CoAP. The idea is that CoMP employs a separate location management function to support CoAP service mobility, and two operating modes, CoMP holding and binding modes, are used for a reliable data transmission during handover. To do this, we have designed the architecture of CoMP. Furthermore, we have designed the detailed signaling flow, the message format and algorithm of CoMP for the mobility support. Finally, the numerical analysis and simulation results of the handover latency and packet loss show the benefits of the proposed protocol.

Massive diffusion of constrained devices communicating through low-power wireless technologies in the future Internet of Things (IoT) will require in many scenarios the deployment of IoT gateways to allow applications to discover and access IoT resources. In this context, Fog/Edge computing will represent an opportunity to deploy IoT gateways in proximity of IoT domains, meeting the requirements of applications needing low-latency interactions with devices. In this paper, we present an edge-centric distributed architecture to provide resource discovery and access services to IoT applications. The proposed approach leverages the CoRE Resource Directory interface and the Constrained Application Protocol (CoAP) to expose a standard interface for global discovery and access. Multiple IoT gateways are federated through a peer-to-peer overlay implemented by a distributed hash table, which is exploited to share the information on IoT resources available across multiple domains. The proposed solution is validated by means of a small-scale prototype, and extensively evaluated through emulation in large scale deployment in comparison to a centralized Cloud-based approach. Experimental results demonstrated that the proposed approach guarantees lower latencies than a centralized solution and can ensure scalability for small to medium sized deployments.

In the contemporary digital era, the Internet of Things (IoT) and its applications have proliferated extensively, particularly within smart city environments, resulting in increased network traffic and raising the significance of efficient service discovery (SD) mechanisms. The social Internet of Things (SIoT) is an emerging paradigm that enables IoT devices to autonomously establish social relationships based on rules defined by their owners, thereby enhancing services through social relations. Things can interact with others; thus, the huge volume of traffic is increased. Each node or device could select an appropriate peer for the discovery of services, which is thus helpful for human beings. Although numerous service discovery and query processing models have been proposed in the recent literature. However, the existing state-of-the-art approaches often lack a comprehensive analysis of the parameters. Most traditional state-of-the-art models primarily focus on relationships or device similarity. Also neglecting the vital factors, for instance, query processing, efficiency, spatial-temporal dynamics, and service provisioning, etc. Thus, to solve this issue, this research proposes an exhaustive analysis of the main parameters needed to implement service discovery mechanisms for Social IoT and studies their relative importance based on a dataset of real objects. Based on the advanced parameters' selection, an efficient service discovery algorithm is proposed. The proposed model emphasizes efficiency by optimizing the service discovery through reduced social graph traversal (i.e., fewer hops), consideration of the service types, and integration of caching mechanisms. We have conducted a comprehensive analysis of key parameters essential for implementing an effective service discovery mechanism in SIoT, prioritizing based on their importance. Experimental validation demonstrates the superiority of the proposed over state-of-the-art models, confirming its efficacy, scalability.

Data communication stack on Internet of Things (IoT)-devices is traditionally implemented in software as a part of their operating systems. In IoT-applications for which resource constrained IoT-devices are deployed, leveraging microprocessor(s) for both computing and data communication tasks may result in poor application performance and high power consumption. In order to alleviate these performance and power issues, using System on Chip (SoC) field programmable gate arrays (FPGAs) for the hardware acceleration of the performance- or power-critical software tasks is a recent, popular trend in the literature. On the other hand, constrained application protocol (CoAP) is a pivotal network protocol for many IoT-applications. Motivated by these facts, in this article, a hardware accelerator for a CoAP server network stack is proposed and realized on a SmartFusion2 SoC FPGA. The hardware accelerated CoAP server network stack is thoroughly evaluated and compared in terms of its performance, latency, power consumption, and FPGA resource utilization against a baseline software implemented CoAP server network stack. The evaluation results obtained clearly show that the CoAP hardware accelerator provides significantly higher performance and lower response message latency, while consuming significantly less power. Consequently, the CoAP hardware accelerator proposed seems to be a strong viable solution for the resource constrained IoT-devices.

The proliferation of the Internet of Things (IoT) has introduced significant challenges in protocol selection for resource-constrained devices operating in smart healthcare, industrial automation, and agricultural monitoring. While lightweight protocols like Message Queuing Telemetry Transport (MQTT) and Constrained Application Protocol (CoAP) are designed for low-power Wide Area Networks, the ubiquity of Hypertext Transfer Protocol (HTTP) persists despite its substantial overhead. This research provides a multi-dimensional performance evaluation of MQTT, CoAP, and HTTP using the NS-3 discrete-event simulator. The study uniquely benchmarks these protocols across nine performance metrics, including Average Latency, Network Jitter, CPU Energy Usage, and Network Footprint, under varying iteration loads (50 and 500) to simulate both nominal and high-stress IoT environments. Our empirical analysis demonstrates that while CoAP provides the highest throughput and lowest resource consumption, MQTT offers superior reliability in persistent monitoring scenarios. Notably, the evaluation reveals a critical scalability threshold for HTTP, where high-stress iterations lead to a complete communication collapse (0% PDR) due to TCP-induced network saturation. By correlating system-level impact (CPU usage) with network-level stability (Jitter), this paper proposes an application-specific decision framework. The findings serve as a technical roadmap for optimizing next-generation IoT deployments based on specific latency and energy requirements.

The Internet of Things (IoT) will connect not only Zigbee-enabled devices but also Wi-Fi-enabled consumer electronics, given the recent rise of IPv6. We developed a power saving communication protocol for low-complexity IPv6-connected devices that can support multiple applications. We demonstrate here in an entertainment-related application scenario how to use that protocol to bring what we refer to as the Internet of Toys to life (Fig. 1). We demonstrate a real-time Internet of Toys system using the Multi-Hop Power Saving Mode (MH-PSM) protocol developed for Wi-Fi enabled IPv6-connected devices on the Contiki OS embedded open source platform [1]. MH-PSM enables low-latency ad hoc communication using 802.11 over multiple hops [2]. The software system includes the RRPL dynamic routing [3] and Constrained Application Protocol (CoAP). The hardware platform is based on low-complexity Arduino Due boards. The system setup includes a gateway, which is an Internet-connected laptop running a CoAP border-router. The toys and gateway create an 802.11 IBSS (ad hoc) network using IPv6. We have implemented an application that enables toys to speak together in coordination (i.e., to engage in a dialog according to a scripted story). The coordination requires signaling between toys. The gateway runs a web server allowing some features of the application to be controlled by a web browser on a phone. The web application creates signaling traffic between the phone and toy(s) which traverses the gateway. The toys can also be monitored and controlled remotely from anywhere in the Internet using CoAP. Fig. 2 shows experimental results when ten toys are active simultaneously transmitting one packet per second to all the other nodes. Such a setup creates a congested environment, with the topology including up to five-hop routes. Comparing the demo setup with an earlier testbed that used MH-PSM [2] with static routes, we note an increase of the delay due to the routing overhead of RRPL. For similar reasons, the packet delivery ratio is also on average 5% lower in the real-time system compared to an earlier evaluation in a testbed. The real-time application clearly introduces new challenges that must be addressed compared to an evaluation in a testbed with predetermined routing tables. However, this application scenario can handle the extra work and the real-time system demonstrates that MH-PSM with RRPL and CoAP can efficiently support a wide range of IoT applications, with packet delivery ratio over 90%. Currently, we are working on moving this platform to support more powerful OpenWrt-enabled devices. In our demonstration, participants can experience the Internet of Toys and use an iPhone (provided) to select a story for the toys to narrate.