Abstract — Messaging protocols are essential components of modern software architectures, enabling efficient communication between various software systems and devices. This paper presents a comparative study of several prominent messaging protocols, including HTTP, WebSockets, WebTransport, WebRTC, MQTT, AMQP, CoAP, STOMP, Matrix and XMPP. These protocols are evaluated and compared based on key criteria such as performance, flexibility, security, and suitability for different use cases. The results of this study aim to guide software architects and developers in selecting the most appropriate protocol for their specific needs.

Keywords — SOTA, Messaging Protocols, HTTP/3, WebSockets, WebTransport, WebRTC, MQTT, AMQP, CoAP, STOMP, Matrix, XMPP

I.     Introduction / Area of research

The IoT (Internet of Things) is growing both in terms of the number of connected devices as well as in the variety of use cases, e.g. smart phones, cars and automation systems [1]. None of these devices have an unlimited amount of battery life or computing power nor can they guarantee permanent network availability. In addition, safety concerns concerning critical environments such as the medicine or industry sector must be considered [2]. This is where protocols come into play. Message protocols allow us to exchange data effectively and reliably between software services respectively devices.

Since 1984, the ISO/OSI (Open Systems Interconnection Model) has been the standard reference model for describing communication across several technical system levels [3]. It consists of seven successive layers. As the interfaces between these layers are clearly defined, the protocol used within a layer is interchangeable. For the web respectively the internet, however, the TCP/IP reference model based on the OSI model is more decisive [4]. It combines several OSI layers, as shown in Fig. 1. The application layer represents the highest level of abstraction and includes all protocols used for exchanging application data such as HTTP or FTP.

Fig. 1 – Layers of OSI and TCP/IP [3], [4]

This paper focuses solely on protocols belonging to the application layer. Though they depend on protocols that are used on lower layers. Protocols were chosen depending on the research taken for openly available protocols that can be used for message exchange between software services/devices.

In general, the protocols examined can be divided into different communication types. Some can be used for Peer-to-Peer (P2P) communication. Others might be classified as message-oriented middleware (MOM) [5]. MOM means that there is no direct data transfer between two clients. Instead, the communication between distributed systems is handled via a message broker or likewise.

II.    Related Work

There are studies that specifically aim to compare IoT protocols at the application layer. The most comprehensive work found is “Investigating Messaging Protocols for the Internet of Things (IoT)” [6]. This paper compares and contrasts the HTTP, MQTT, CoAP, AMQP, XMPP and DDS protocol. No papers were found that would provide a more complete analysis featuring further protocols. Referenced works such as “Choice of Effective Messaging Protocols for IoT Systems: MQTT, CoAP, AMQP and HTTP” [7], take a similar approach for the comparison. Both works collect the protocol properties in a table containing for example the release year, the application purpose and its architecture. However, comparisons that do also include other web protocols such as WebTransport are missing.

III.   Methodology

Protocols of interest were determined through browsing for related work starting with the term “messaging protocols”. Sources for the research were IEEE, Google Scholar and Google Search. After a protocol was identified as significant for this paper the associated specification was searched up. Additionally, at least two further trustworthy sources from IEE or Google Scholar were determined per protocol.

IV.   comparison analysis

This chapter serves to present the investigated protocols. Mentioned RFC (Requests for Comments) refer to the technical documentations published by the Internet Engineering Task Force (IETF) [8]. The IETF is the premiere standards development organization for the Internet. The international organization for standardization (ISO) on the other hand is a more formal and not internet specific institution that has 169 national standardization bodies as members [9].

A.    HTTP/3 (RFC9114 [10])

Today, the Hypertext Transfer Protocol (HTTP) is the basis for communication across the internet [11]. It is a stateless protocol based on a request-response model. A client sends a message, and a host/server generates a response message. The first version of HTTP was standardized in 1997, followed by HTTP/2 in 2014. Finally, 2022 the standard of HTTP/3 was introduced. Under the hood HTTP/3 uses QUIC and the UDP protocol on the transport layer and therefore is able to solve line blocking problems that occurred in previous HTTP versions that use TCP for multiplexing [12].

QUIC (Quick UDP Internet Connections), standardized in RFC 9000 [13], was initially developed by Google in 2012 and became a standard in 2021 [14]. While TCP allows reliable ordered and error-checked delivery of data, UDP sends datagrams without establishing a connection. Therefore, it is more lightweight and faster than TCP but at the same time cannot guarantee package delivery or order. QUIC however builds up on top of UDP solving these issues and trying to replace TCP in a faster, more secure and reliable way.

Fig. 2 – HTTP Protocol Stack [11]

With HTTP there are several popular choices available for building API’s (Application Programming Interfaces) [15]. These include SOAP, REST, gRPC and GraphQL. According to the Postman state of the API 2023 survey report [16] REST is the most used pattern with 86% of respondents using it.

B.    WebSocket (RFC6455 [17]), WebTransport (RFC draft [18]) & WebRTC (RFC8831 [19])

WebSockets can be used to establish bi-directional data channels between clients and a server [20]. The WebSocket standard was introduced in 2012. Like HTTP/2 it depends on TCP. Messages are handled via a single ordered reliable stream. This means that messages must be sent and received in order. The consequence is that WebSocket’s are a bad choice for latency-sensitive applications.

A kind of successor to WebSockets is the WebTransport protocol [21]. Since 2021 the standard for WebTransport has been under development. The big advantage over WebSockets is the ability to create a bidirectional multiplexed communication channel. Through datagrams unreliable unordered data such as real-time audio or video frames can be sent and received. Additionally, streams can be used to send and receive reliable ordered data.

WebSocket and WebTransport can be used for real-time client-to-server communication. However, in some cases it might be necessary to create such a connection for p2p (browser to browser) data transmission [22]. For this scenario, WebRTC can be used. A possible use case is for example a video call.

C.   CoAP (RFC7252 [23])

The CoAP standard was published in 2014. It was designed for the use within constrained (e.g., low-power, lossy) networks and low performance devices [24]. Machine-to-machine (M2M) applications like smart energy and building automation are the preferred fields of application. However, the protocol can easily interoperate with HTTP via a proxy to provide a web interface. Therefore, the protocol realizes a subset of the REST (Representational State Transfer) architectural pattern and is based on a request/response interaction model between a server and clients. In addition, features like asynchronous message delivery, device discovery or multicast support are implemented. UDP is used as the default transportation method but also TCP or SMS are possible options. Endpoints are defined by an URI (e.g., coap://localhost:5683/device_name/parameter). Messages can be secured with DTLS.

D.   MQTT (ISO/IEC 20922:2016 [25])

After the protocols already presented, we now for the first-time encounter with MQTT a MOM (Message Oriented Middleware) based approach that can be used for many-to-many communication [26]. The invention of MQTT dates to 1999. Nevertheless, it was not freely available until 2010.  2014 MQTT became an official OASIS standard. Furthermore, MQTT v3.1.1 is an international standard (ISO/IEC 20922:2016). In 2019 the MQTT v5 standard [27] was ratified. MQTT is a platform-oriented, simple to implement and lightweight protocol that can be used in many different situations [28]. Because of its small footprint MQTT is a perfect match for low-power and low-memory devices. Use case examples are manufacturing systems, logistics, enterprise chat applications and mobile apps. In earlier versions MQTT referred to MQ Telemetry support, but nowadays it is no longer considered an acronym. The protocol is based on a publish/subscription model where clients subscribe or publish to a specific topic. A Message Broker is used to handle the incoming requests [29]. Also see Fig. 3 – MQTT Publish/Subscribe Model [28]. A broker  is available from, for example, EMQX, HiveMQ, RabbitMQ or Mosquito. As an underlying protocol there are several options available. The default is TCP, WebSocket’s can be used for connecting over a web browser and QUIC is the latest available option [14].

Fig. 3 – MQTT Publish/Subscribe Model [28]

E.    AMQP (ISO/IEC 19464:2014 [30])

OASIS introduced the first version of the Advanced Message Queuing Protocol (AMQP) standard in 2012 [31]. Like for MQTT there exists an international standard (ISO/IEC 19464:2014). It defines itself as an internet protocol for business messaging and uses a MOM based approach [32]. It was specifically designed for the finance sector to address business processes, message transactions and applications. For this a reliable protocol on the transport layer such as TCP or QUIC is assumed. Similar to MQTT, messages are exchanged via a broker [33]. The main difference lies in the usage of message queues. In MQTT a published message would be directly routed to subscribers. In AMQP though published messages are first handled by an exchange component. Depending on the configuration (like routing keys and message type) messages are added to the corresponding message queues [34]. There it will be stored until a consumer consumes it. See Fig. 4 – AMQP core concept [34]. Examples for AMQP message brokers are RabbitMQ, SwiftMQ, Azure Service Bus and Apache Artemis. Message queues are an essential concept to make software scalable, resilient and working asynchronously.

Fig. 4 – AMQP core concept [34]

F.    STOMP

STOMP (Simple Text Oriented Message Protocol) [35] is designed to work with message-oriented middleware [36]. Whereas  MQTT and AMQP are binary protocols, STOMP is text-based. Due to the human-readable text-format STOMP is simpler and therefore easier to implement than other messaging protocols. Commonly it is used for real-time messaging in distributed systems. Supported messaging servers that support STOMP are for example RabbitMQ or EMQX via a Gateway. The communication between a client and the server is handled through a frame modelled on HTTP. The first line of the frame contains the command, followed by headers like username and password. The last line is the message body. Destination addresses, transportation protocol and security depend on the used server respectively message broker.

G.   XMPP (RFC6120 [37])

XMPP (eXtensible Messaging and Presence Protocol) or formerly Jabber enables near-real-time exchange of data  [38]. Popular use cases are instant messaging, multi-party chat, voice and video calls as seen in applications like WhatsApp or Facebook. The protocol was mainly developed in 1999 and was standardized the first time in 2004. In 2012 the latest revision RFC6120 was introduced. XMPP uses XML (Extensible Markup Language) as the data-exchange format and is based on a client/server architecture. Furthermore, it uses TCP on the transportation layer. For the XMPP Server there are many options available, e.g., Tigase and ejabberd. Users on the network are addressed by email like identifiers called JID’s. One of its strengths compared to MQTT is the build in end-to-end encryption.

H.   Matrix

An alternative to XMPP for instant messaging is Matrix [39]. It was introduced in 2014 and is an open standard. Compared to XMPP it is generally seen more usable for group organization platforms like Slack [40]. Matrix supports bridging to other messaging platforms such as XMPP servers, Email and SMS enabling a unified way of communication. Matrix is also considered to be more secure than, for example, WhatsApp. The French government uses Matrix as base for their own communication platform called Tchap that is used for the communication of government officials and civil servants. The world wide web currently lacks on scientific papers observing this protocol.

V.    Conclusion

In summary, all explored protocols have their unique strengths and weaknesses. In practice, this is why multiple protocols are used together to achieve the development goals of a new application. With the rise of new technologies and the gain in the number of internet devices more and more protocols will emerge. Furthermore, the existing protocol standards will evolve as well. QUIC is the best example for this. It was standardized in 2021 and was then used as transportation method of HTTP/3. Other technologies like MQTT start profiting from the advantages of QUIC over TCP. These developments leave room for future research in this sector. In addition, detailed research of the protocol usage in different programming environments can be conducted to identify missing links and gain a deeper understanding of the inner workings of web technologies and protocols in general. To conclude Fig. 5 – Covered Protocols Summary contains the summary of the protocols that were covered by this paper.

Fig. 5 – Covered Protocols Summary

Acknowledgment

This paper was written as part of the master class Mobile in the master program Interactive Technologies at the UAS St.Pölten. It was revised based on the feedback from fellow students.

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Keywords—5G, Mobile Development, App Development, technology

I. INTRODUCTION

The revolution of mobile communication technologies has undergone a notable transformation over different generations, continually expanding the horizons of mobile application development. Starting with 2G’s introduction of digital voice communication and culminating in the widespread adoption of 4G, which facilitated faster data transfer and mobile internet access, each generation has marked a stride towards innovation [1].

The fifth generation of mobile networks, 5G, indicates a paradigmatic leap in mobile technology. Distinguished by remarkable data transfer speeds, reduced latency, and increased network capacity, 5G stands as the central trigger for a new era in mobile application development. Beyond a mere incremental upgrade, it represents a technological leap promising to redefine the scope of mobile applications [2].

This article seeks to explain the multifaceted impact of 5G on mobile application development. Going beyond technical specifications, it aims to solve the implications for developers, enterprises, and end-users. Specifically, it will analyse how enhanced connectivity and reduced latency influence the performance of existing applications, while also paving the way for innovative applications across diverse sectors of the economy [1] [2].

II. ENHANCED CONNECTIVITY

The origin of 5G technology signifies a revolutionary period in mobile connectivity, fundamentally changing the way in which mobile applications harness and leverage network capabilities. With data transfer speeds attaining remarkable levels, 5G is not only an incremental improvement but a force redefining connectivity in the mobile application development environment [3].

A. Accelerating Towards the Future

The impact of 5G on mobile application development is summarized in its ability to provide ultra-fast data transfer speeds. The transition from 4G to 5G signifies a jump from megabit to gigabit per second, empowering applications to seamlessly deliver high-definition content, facilitate real-time communication, and manage massive data transfers with exceptional efficiency. This leap transcends faster downloads, showing in new possibilities for interactive applications previously constrained by slower network speeds [4].

Recent studies [5] claim a positive correlation between the increased data transfer speeds of 5G and enhanced user engagement. For instance, video streaming applications can now offer higher resolution and smoother playback experiences, contributing to better user satisfaction and longer application usage.

B. Seamless Connectivity in Real Time

The enhanced connectivity of 5G transcends speed, displaying as a real-time, connected experience for users. The reduced latency offered by 5G minimizes the temporal gap between user actions and application responses. Applications reliant on immediate interactions, such as online gaming and augmented reality, derive immense benefit from this low-latency environment [6].

Picture a collaborative virtual reality application where users across different locations seamlessly interact in real time. 5G sets this vision by shortening data transmission delays, resulting in an immersive and synchronous experience for users. This level of real-time interactivity facilitates innovative applications across various sectors, from collaborative business tools to virtual classrooms [6].

C. Unleashing High-Volume Data Potency

The boosted network capacity of 5G is a game-changer for applications requiring large-scale data transfers. Sectors relying on extensive data sets, such as healthcare and autonomous vehicles, can make use of the full potential of 5G to efficiently transfer and process data. For instance, in healthcare, high-resolution medical imaging can be transmitted in real time, facilitating remote diagnosis and collaboration among healthcare professionals [7].

5G enables mobile applications to effortlessly process significant data volumes, not only enhancing existing applications but also laying the groundwork for the development of previously unimaginable applications due to bandwidth constraints [7].

The impact of 5G on connectivity enhancement extends beyond speed improvements, creating a dynamic environment where applications operate in real time, effortlessly process large volumes of data, and deliver transformative user experiences. As we examine further, it becomes clear that 5G’s enhanced connectivity is not simply a technological upgrade, but a game changer that unlocks unknown possibilities for the future of mobile application development [7].

III. REDUCED LATENCY

Reduced latency stands out as one of the main features of 5G technology, indicating a significant upgrade in the responsiveness and interactivity of mobile applications. This section explores the numerous implications of latency reduction, explaining how it not only speed up the performance of existing applications but also serves as a trigger for the development of innovative, latency-sensitive applications.

A. The Latency Revolution

Reducing latency in 5G networks acts as a gateway to a new domain of possibilities for mobile application development. Latency, meaning the time taken for data to travel from the user’s device to the server and back, has historically posed a significant barrier to applications requiring real-time interaction. 5G, with its markedly reduced latency in comparison to its ancestors, is reshaping the user experience, especially in applications where split-second responses are important [8].

Recent experiments [9] conducted on 5G networks showcase a remarkable reduction in latency, frequently reaching single-digit milliseconds. This upgraded level of responsiveness is transformative for applications such as augmented reality (AR) and virtual reality (VR), where even the slightest delay can disrupt the immersive experience. The newfound ability to provide near-instantaneous responses lays the groundwork for more advanced and immersive applications, positioning 5G as a technology enabler for the next generation of user interfaces.

B. Gaming in the Blink of an Eye

The online gaming sector stands as one of the primary inheritors of the reduced latency offered by 5G. Near-instantaneous communication between the player’s device and the game server ensures that actions are executed with minimal delay. This not only enhances the gaming experience by rendering it more responsive but also facilitates the expansion of cloud gaming services, where the entire game is streamed in real time to the user’s device [10].

Furthermore, the reduced latency in 5G paves the way for multiplayer virtual reality gaming experiences that blur the line between the physical and digital realms. Players can interact with each other in real time, enabling a level of immersion that was previously impeded by latency constraints [10].

C. Augmented Reality Unleashed

The potential of reduced latency becomes even more evident in augmented reality applications. 5G’s ability to minimize the delay between a user’s actions and the corresponding AR overlay results in a seamless and engaging experience. For example, in navigation applications, users can receive AR directions in real time with unnoticeable delay, thereby enhancing both safety and user satisfaction [11].

Reducing latency is not just a technological breakthrough, it transforms the way users interact with applications. Whether in gaming, AR, or other latency-sensitive applications, 5G is facilitating a new era of instantaneous and immersive experiences that were considered limited by the restrictions of prior network generations [11].

The reduction in latency, inherent to 5G, stands as the driving force of its impact on mobile application development. It accelerates the evolution of existent applications, particularly in gaming and augmented reality, and lays the foundation for the creation of entirely new latency-sensitive applications. As we navigate this terrain of reduced latency, it becomes evident that 5G is not solely about speed but a revolutionary transformation in how users engage with and experience mobile applications [11].

IV. NEW TYPES OF APPLICATIONS

The transformative potential of 5G extends beyond the optimization of existing applications. It serves as a motivation for the invention of entirely unknown and innovative applications across various sectors. In this section, we investigate the far-reaching implications of 5G in propelling the development of new types of applications, revolutionizing sectors such as healthcare, education, and automotive.

A. Healthcare at 5G Speed

Healthcare stands as one of the fields most impacted by the innovation caused by 5G. The high speed and low latency of 5G open opportunities for applications previously considered impractical. Remote surgery, also known as telesurgery, is becoming a doable option with 5G connectivity. Surgeons can operate on patients situated in different geographical locations with minimal delay, facilitated by high-definition video streams and real-time haptic feedback [12].

Beyond telesurgery, 5G facilitates the real-time communication of extensive medical data sets, enabling healthcare professionals to instantaneously access and analyse high-resolution images. This bears profound implications for diagnosis and collaboration, enhancing the efficiency and precision of medical interventions [7].

B. Education Transformed

In the sector of education, 5G is generating a monumental development. The combination of enhanced connectivity and reduced latency enables immersive and interactive learning experiences. Virtual classrooms can be brought to life with real-time video streaming, collaboration tools, and augmented reality applications. Imagine students participating in virtual field trips, exploring ancient sites, or conducting virtual experiments in science labs, all facilitated by the capabilities of 5G [13].

Furthermore, 5G is pushing the addition of personalized learning applications that dynamically adapt to the individual needs of students. These applications leverage high-speed connectivity to instantaneously deliver content, assessments, and feedback, thereby creating a dynamic and responsive learning environment [13].

C. Automotive Innovation

The automotive industry is undergoing a deep transition with the advent of 5G. In addition to enabling faster, more reliable connectivity in cars, 5G serves as the foundation for the development of autonomous vehicles. Low-latency communication between vehicles and infrastructure facilitates real-time data exchange, augmenting the capabilities of autonomous cars [14].

5G connectivity simplifies vehicle-to-everything (V2X) communication, enabling cars not only to communicate with each other but also with traffic lights, pedestrians, and other elements of the urban environment. This connected communications ecosystem lays the groundwork for safer and more efficient transport systems [14].

D. Gaming Beyond Boundaries

The gaming industry is experiencing a revival with 5G, beating traditional gaming paradigms. Cloud gaming services, where the entire gaming experience is streamed in real time to the user’s device, are becoming more feasible thanks to 5G’s speed and low-latency characteristics. Gamers can access and play resource-intensive games without the need for powerful hardware, opening new possibilities for accessibility and engagement [8].

Moreover, 5G is facilitating the emergence of augmented reality (AR) and virtual reality (VR) gaming experiences that seamlessly combine the digital and physical worlds. Gamers can explore interactive and immersive environments with greater realism than ever before, creating a new frontier for the gaming industry [8].

The impact of 5G on new types of applications is profound and transformative. From healthcare and education to automotive and gaming, 5G generate new routes for innovation. As we witness the emergence of applications once bounded by technological limitations, it becomes evident that 5G is not just an evolution of connectivity, it is a trigger for reshaping the core fabric of our digital experiences [8].

V. CONCLUSION

In conclusion, 5G technology stands as a transformative force in mobile application development, redefining user experiences and enabling innovation. Beyond its remarkable speed and connectivity, 5G’s impact extends to reducing latency, giving rise to new immersive applications. From healthcare to education, automotive to gaming, 5G is a force propelling revolutionary possibilities.

The improved connectivity of 5G redefines user experiences, offering faster data transfer speeds and increased network capacity [15]. Reduced latency not only accelerate existing applications but also produces new experiences in gaming and augmented reality [9]. Additionally, 5G opens the door to entirely new applications, transforming the healthcare, education, and automotive sectors [12]-[14].

Navigating this dynamic landscape, it is evident that 5G not only transcends an upgrade, but it also constitutes a revolution in mobile communication technologies. Researchers and developers are poised to explore uncharted territories, anticipating new advances that will develop the future of mobile experiences. The transition from 2G to 5G reflects a journey marked by continuous innovation, with 5G serving as the canvas upon which the next chapter in mobile application development is unfolding.

REFERENCES

[1]          Salih, A., Zeebaree, S., Abdulraheem, A., Zebari, R., M.Sadeeq, M., & Ahmed, O. (2020). Evolution of Mobile Wireless Communication to 5G Revolution. Technology Reports of Kansai University, 62, 2139–2151.

[2]          Gohar, A., & Nencioni, G. (2021). The Role of 5G Technologies in a Smart City: The Case for Intelligent Transportation System. Sustainability, 13(9), Article 9. https://doi.org/10.3390/su13095188

[3]          The Intersection of 5G and Mobile App Development—SegWitz. (2023, September 6). https://segwitz.com/5g-and-mobile-app-development/

[4]          Temesvari, Z., Maros, D., & Kadar, P. (2019). Review of Mobile Communication and the 5G in Manufacturing. Procedia Manufacturing, 32, 600–612. https://doi.org/10.1016/j.promfg.2019.02.259

[5]          Kim, Y. H., Kim, D., & Wachter, K. (2013). A study of mobile user engagement (MoEN): Engagement motivations, perceived value, satisfaction, and continued engagement intention. Decision Support Systems, 56, 361–370. https://doi.org/10.1016/j.dss.2013.07.002

[6]          Qiao, X., Ren, P., Nan, G., Liu, L., Dustdar, S., & Chen, J. (2019). Mobile web augmented reality in 5G and beyond: Challenges, opportunities, and future directions. China Communications, 16(9), 141–154. https://doi.org/10.23919/JCC.2019.09.010

[7]          Georgiou, K. E., Georgiou, E., & Satava, R. M. (2021). 5G Use in Healthcare: The Future is Present. JSLS : Journal of the Society of Laparoscopic & Robotic Surgeons, 25(4), e2021.00064. https://doi.org/10.4293/JSLS.2021.00064

[8]          root. (2023, July 19). The Rise of 5G and Impact on Mobile App Development—itCraft blog. Mobile & Web App Development Company | USA, UK, Norway. https://itcraftapps.com/blog/the-rise-of-5g-and-impact-on-mobile-app-development/

[9]          Skocaj, M., Conserva, F., Grande, N. S., Orsi, A., Micheli, D., Ghinamo, G., Bizzarri, S., & Verdone, R. (2023). Data-driven Predictive Latency for 5G: A Theoretical and Experimental Analysis Using Network Measurements. 2023 IEEE 34th Annual International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC), 1–6. https://doi.org/10.1109/PIMRC56721.2023.10293861

[10]        Evolving Mobile cloud gaming—Mobility Report. (n.d.). Retrieved 22 November 2023, from https://www.ericsson.com/en/reports-and-papers/mobility-report/articles/mobile-cloud-gaming

[11]        Siriwardhana, Y., Porambage, P., Liyanage, M., & Ylianttila, M. (2021). A Survey on Mobile Augmented Reality With 5G Mobile Edge Computing: Architectures, Applications, and Technical Aspects. IEEE Communications Surveys & Tutorials, PP. https://doi.org/10.1109/COMST.2021.3061981

[12]        Cabanillas-Carbonell, M., Pérez-Martínez, J., & Yáñez, J. (2023). 5G Technology in the Digital Transformation of Healthcare, a Systematic Review. Sustainability, 15, 3178. https://doi.org/10.3390/su15043178

[13]        Sustainability | Free Full-Text | Transforming Education: A Comprehensive Review of Generative Artificial Intelligence in Educational Settings through Bibliometric and Content Analysis. (n.d.). Retrieved 22 November 2023, from https://www.mdpi.com/2071-1050/15/17/12983

[14]        Biswas, A., & Wang, H.-C. (2023). Autonomous Vehicles Enabled by the Integration of IoT, Edge Intelligence, 5G, and Blockchain. Sensors, 23(4), Article 4. https://doi.org/10.3390/s23041963

[15]        (8) The Impact of 5G on App Development and User Experience | LinkedIn. (n.d.). Retrieved 22 November 2023, from https://www.linkedin.com/pulse/impact-5g-app-development-user-experience-subcodevs/

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Allgemein

Im Zeitalter des digitalen Wandels und des zunehmenden Vorstoßes mobiler Technologien ergeben sich laufend neue Anwendungsfelder bei denen ganze Geschäftsprozesse von mobilen Applikationen abgewickelt werden. Auch im Einsatzwesen, wo ein rascher Datenaustausch von besonders hoher Wichtigkeit ist, können mobile Dienste zu einer entscheidenden Wertsteigerung führen, indem Koordination und Kommunikation verbessert werden.

Meine Diplomarbeit befasst sich mit der Fragestellung, inwieweit mobile Anwendungen im Einsatzwesen, speziell im Anwendungsbereich von Feuerwehren, einen Nutzen bringen können. Dabei konzentriert sich die Forschung vorwiegend auf das Atemschutzwesen.

Die Bedeutung des Atemschutzes im Feuerwehrwesen

Dem Atemschutzwesen wird in der Feuerwehr künftig eine immer wichtiger werdende Bedeutung beigemessen. Zudem wird der Einsatz von schwerem Atemschutzgerät auch immer unabdingbarer, da bei fast allen Brandeinsätzen hochgiftige Brandfolgeprodukte, wie Gase, Dämpfe oder Ruß entstehen. Ganz allgemein zählt das Atemschutzwesen zu den gefährlichsten Tätigkeiten während eines Einsatzes. Aus diesem Grund unterliegt der Einsatz von Atemschutzkräften auch besonders strengen Sicherheitsvorkehrungen. Dazu gehört unter anderem eine kontinuierliche Atemschutzüberwachung (kurz: ASÜ), die einen klareren Überblick sowie eine genaue Koordination der eingesetzten Kräfte und ihrer vorhandene Atemluft ermöglicht. Konkret versteht man darunter die zeitliche Überwachung der eingesetzten Kräfte während eines Atemschutzeinsatzes.

In den vergangenen Jahrzehnten hat sich in Österreich eine Vielzahl an unterschiedlichen Systemen hinsichtlich der ASÜ etabliert. So reicht heute die Produktpalette von der simplen Methode mittels Stift und Papier bis hin zu modernen Softwarelösungen.

Der klassische Vorgang der Atemschutzüberwachung findet in Österreich meist noch immer analog, also mit Stift und Papier, oder anhand einfacher elektronischer Hilfsmittel statt (siehe Abbildung oberhalb). Dabei werden zu Einsatzbeginn alle notwendigen Einsatzparameter wie die Flaschenfülldrücke oder die Einsatzzeiten handschriftlich erfasst. Häufig wird auch eine Stoppuhr gestellt, um jederzeit einen Überblick über die restliche Einsatzzeit zu haben. Diese Vorgehensweise ist meist mit sehr viel Schreibarbeit verbunden und daher nicht nur zeitraubend, sondern auch sehr fehleranfällig, vor allem bei der Überwachung mehrerer Trupps.
Es gibt derzeit nur wenige elektronische Überwachungssysteme bei denen bestimmte Daten automatisch berechnet, aktualisiert und dementsprechend visualisiert werden.
Nach dem bis zum jetzigen Zeitpunkt, zumindest im deutschsprachigem Raum, noch keine mobile Smartphone-App für die Atemschutzüberwachung existiert, hab ich mir das Ziel gesetzt, eine zu entwickeln, um diese Lücke zu schließen.

Methodik

Recherche

Um vorerst einen genaueren Einblick über den aktuellen Stand der Technik zu erlangen, und gleichzeitig eine weitere Grundlage für den empirischen Teil dieser Diplomarbeit zu schaffen, wurde eine Recherche getätigt um Einsicht darüber zu erlangen, welche unterschiedlichen Geräte und Methoden für die ASÜ bereits existieren.
Wie schon erwähnt, gibt es eine Vielzahl an derartigen Systemen. Die Grundfunktionalität jedoch, ist bei allen Systemen die gleiche.

Ein ASÜ-System besteht somit aus folgender Grundfunktionalität

• Vor- und Nachname der eingesetzten Atemschutzträger müssen festgehalten werden können.
• Die aktuelle Uhrzeit muss ablesbar sein. Bei den meisten Systemen ist für diesen Zweck eine kleine digitale Uhr integriert.
• Flaschendruck zu Einsatzbeginn: Zu Beginn des Einsatzes wird der niedrigste Flaschendruck der drei Atemschutzträger notiert.
• Messung der Einsatzzeit pro eingesetzten Trupp: Zu Einsatzbeginn wird begonnen, die Einsatzzeit zu stoppen. Auf diese Weise soll in Echtzeit ein grober Überblick darüber entstehen, wie viel Restzeit dem jeweiligen Trupp noch zur Verfügung steht.
• Festhalten der Bezeichnung bzw. des Funkrufnamens (= eindeutige Bezeichnung für einen Trupp) des jeweiligen Trupps: Jeder eingesetzte Atemschutztrupp muss mit einem eindeutigem Namen versehen werden.

Anforderungsanalyse

Die anhand der Recherche gewonnenen Erkenntnisse in Bezug auf die Grundfunktionalität waren mir im Vorfeld der technischen Implementierung noch nicht ausreichend, sodass ich mich entschied eine Anforderungsanalyse in der Form von Expertengesprächen durchzuführen.

Das Ziel dieser Experteninterviews war die Verfassung eines möglichst umfangreichen Anforderungsdokumentes als fundamentale Grundlage für die nachfolgende technische Umsetzung der mobilen Anwendung.
Konkret ergaben sich so eine Reihe funktionaler Anforderungen sowie unterschiedliche Bedarfe an die Usability.

Technische Implementation

Im Anschluss wurde eine native Android-App konzipiert und technisch umgesetzt. Die wichtigsten Funktionen werden nachfolgend erläutert.

In der Listenansicht kann die Benutzerin/ der Benutzer die bereits angelegten Atemschutzträger samt allen gespeicherten Parametern. Das “Personen-Symbol” soll in einer künftigeren Version durch ein Profilbild ersetzt werden.

Am unteren Bildschirmrand befindet sich ein Plus-Symbol. Klickt man darauf, so gelangt man auf eine neue Ansicht, in der man schließlich ein neues Profil anlegen kann.

Natürlich kann man auch Trupps anlegen und diesem die Atemschutzträger zuordnen, wie die nachstehenden beiden Abbildungen veranschaulichen.

Das eigentliche „Herzstück“ der App ist die Truppdetailansicht. Hier wird die aktuell verfügbare Atemluft anhand eines Balkendiagrammes visualisierst.

Drückt die Benutzerin/ der Benutzer nun auf die Schaltfläche „Einsatz starten“, so wird die Einsatzzeit anhand der zuvor eingegebenen Atemluftmenge berechnet und in Echtzeit aktualisiert, wie der blaue Balken auch.        
Die Einsatzzeit wird dabei wie folgt berechnet:                   
Der Luftverbrauch bei körperlich mittelmäßig anstrengender Arbeit in einem Feuerwehreinsatz wird vom österreichischen Bundesfeuerwehrverband mit 50 Liter Atemluft pro Minute kalkuliert – das entspricht exakt 6,25 Bar pro Minute.
Sinkt die Menge der Atemluft unter 60 Bar, so gibt die App einen Alarmton aus (Restdruckwarnung). 
Selbstverständlich kann der Flaschenfülldruck auch während einem laufendem Einsatz nachkorrigiert werden.

Usability Tests

Um die Einsatztauglichkeit der App zu testen, wurden zehn Usabilitytest mit Vertretern unterschiedlicher Feuerwehren durchgeführt. Dabei wurden einige Optimierungspotentiale für eine künftige Weiterentwicklung gefunden. Außerdem ergab sich ein SUS-Score von 82 Punkten (maximal 100) und eine durchschnittlicher Task-Success von 1,36 (Wertungsskala von 1 bis 4, 1 = beste Note).

Fazit

Der Einsatz von mobilen Endgeräten wird in Wirtschaft und Industrie immer alltäglicher. So ist es auch denkbar, dass sich auch Feuerwehren künftig immer häufiger mit Tablets und Smartphones ausstatten, um Einsätze besser bewältigen zu können. In diesem Zusammenhang ist es auch sehr naheliegend, dass die Atemschutzüberwachung künftig über eine mobile Anwendung erfolgt. Der wesentliche Teil der App konnte bereits im Rahmen dieser Arbeit realisiert werden, sodass diese Version bereits einsatzfähig ist. Unabhängig davon lässt sie aber zum jetzigen Zeitpunkt noch einen großen Spielraum für mögliche Erweiterungen.

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In diesem Paper wird das Konzept und ein Prototyp eines Step-by-Step basierten Inhouse-Navigationssystems vorgestellt, welches aus technischen und finanziellen Gründen auf eine kontinuierliche Positionserkennung verzichtet und mit vergleichsweise geringem Aufwand an neuen Orten eingeführt werden kann. Im Vorfeld wurden in einer intensiven Recherche bestehende Systeme zur Positionsbestimmung in Gebäuden analysiert und auf ihre Zuverlässigkeit und Flexibilität untersucht. Diese Parameter führten zur Entscheidung, die Positionsbestimmung auf der Basis von künstlich angebrachten, visuellen Landmarks in Form von QR (Quick Response)-Codes zu realisieren. Eine mögliche Erweiterung durch Echtzeit-Lokalisierungssysteme wird jedoch nicht ausgeschlossen. Die Routingberechnung basiert auf dem Setzen von Knoten an Start-, Endpunkten und Abzweigungen sowie Kanten, die diese Knoten verbinden. Jeder Kante wird dabei nach Länge und Art eine Gewichtung zugeordnet, aufgrund derer mit Hilfe des Dijkstra-Algorithmus der kürzeste Weg zwischen zwei Knoten berechnet wird. Weitere Parameter bieten die Möglichkeit, auf die Routenberechnung einzuwirken und ermöglichen so eine Prioritätensetzung und im Bedarfsfall Barrierefreiheit bei der Navigation. Mit Hilfe eines einfachen Backends für die Erstellung eines Routing-Netzwerkes für ein neues Gebäude, können die Einrichtungskosten auf einem Minimum gehalten werden. Durch Klicken in einer Karte des Gebäudegrundrisses können schnell Wegzüge erstellt und durch Auswahl aus vordefinierten Knoten- und Kantenkategorien einfach parametrisiert werden. Um die Navigation anhand der berechneten Route für Smartphone-BenutzerInnen verständlich zu machen, wird die Route in kleinen, übersichtlichen Schritten (Steps) dargestellt, die sowohl auf einer maßstabsgetreuen Karte, wie auch als dynamisch generierter Text angezeigt werden. Die Zielsuche wird dabei durch eine Auswahlliste anhand von Knotenkategorien (Büro, Seminarraum, WC, …) erheblich erleichtert. Anhand eines Sets von Usabilitytests wird gezeigt, dass das System, bestehend aus den QR-Codes zur Positionsfindung und einer Smartphone-Anwendung zur Navigation, von BenutzerInnen ad hoc verstanden wird und zur Navigation innerhalb von den BenutzerInnen unbekannten Gebäuden eingesetzt werden kann.

Publikation und Präsentation stehen zum Download bereit:

Paper Forum Medientechnik 2013

Präsentation Forum Medientechnik 2013

Autoren

Ewald Wieser, Tomas Kasanicky, Florian Schiesterl, Bernhard Griessler, Christoph Fabritz, Kerstin Blumenstein, Grischa Schmiedl

Zitieren als

Wieser, E., Kasanicky, K., Schiesterl F., Grießler, B., Fabritz C., Blumenstein K. & Schmiedl, G., 2013. Smartphonebasierte Step-by-Step Indoor-Navigationslösung ohne kontinuierliche Positionserkennung. In Forum Medientechnik – Next Generation, New Ideas. St. Pölten: Fachhochschule St. Pölten.

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Die Session “Offline (mobile) Webdevelopment auf der Developer Week 2013 in Nürnberg zeigte die Möglichkeiten und Limitationen aktueller JavaScript-APIs im Umfeld von HTML 5 zur Offline-Nutzung für Webapplikationen anhand von Praxisbeispiele auf.

Präsentation Developer Week / Nürnberg, Deutschland (2013):
Download Präsentation
Download Code

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Context Based Computing bedeutet:

• dem richtigen User

• zur richtigen Zeit

• aktuell relevante (und richtige) Information

• in einem an die Situation angepassten Format zu geben.

Im Gegensatz zu stationären Computern (und dazu zähle ich auch Noteboks) werden Smartphones häufig tatsächlich “on the move” eingesetzt. Je nach Szenario sind manche Applikationen sogar nur in einem mobilen Szenario sinnvoll. Aber nicht alle Applikationen sind für diesen mobilen Kontext geeignet bzw. in der Lage diesen zu erkennen und dem User eine kontext-sensitive User Experience anzubieten.

Daraus ergeben sich eine Vielzahl an Fragen und Forschungsthemen:

A) Bewährt sich meine App in einem mobilen Szenario, in dem sich der User nicht ausschließlich der App widmen kann, sondern sich auch auf die Umwelt (den Context) konzentrieren muss – um z.B. beim Gehen nicht mit anderen Personen oder Gegenständen zu kollidieren?

Diese Thema wurde in folgenden Artikeln behandelt:

• Paper CHI Sparks / Han, Niederlande (2011): Usability Testing for mobile scenarios of fragmented Attention
• Paper Forum Medientechnik / St. Pölten (2012): Usability Testing mobiler Szenarien als Sekundärtask

B) Welche Sensoren helfen mir den Context des Users zu ermitteln und wie lassen sich Sensordaten intelligent verknüpfen und interpretieren.

Beide Themen wurden auf der Developer Week / Mobile Developer Conference in Nürnberg im Juni 2013 vorgestellt.

Präsentation Developer Week / Nürnberg, Deutschland (2013): Download Presentation

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Download Volltext: Mobilot FMT Paper

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