Over the past 10 years online video streaming has seen a tremendous increase in popularity, as it has become a great source of both entertainment and education. This increase in popularity has led to demands for higher quality streams, shorter buffering time and service adaptivity, based on the user’s personal prerequisites. These demands together with a constant increase in Internet usage have posed several challenges for streaming service providers to overcome. Within this master thesis an exploratory research and development project has been conducted. The project’s purpose has been to investigate common approaches, standards and trends related to establishing a multimedia streaming service. Based on the results from these investigations, the purpose has furthermore been to design and implement a proof-of-concept streaming server fulfilling the thesis internship company’s needs and requirements. Research has concluded that there are at least five vital components, which have to be carefully considered in order to establish a successful streaming service. These vital components are; the service system structure, the service application programming interface (API), the service hosting solution, the service data storage solution and finally the actual streaming module. Based on results from conducted investigations of common design approaches for each vital component, decisions for the thesis project implementation have been made. The resulting system has been built using the event-based system structure framework Node.js. A representational state transfer (REST) API has furthermore been implemented for managing client request routing. The resulting system has been implemented on a self-hosted server solution even though this is neither a preferred choice in theory nor common practice. The decision has however been made due to future plans at the thesis internship company of investing in a corporate-wide cloud-based server solution. For the service data storage solution the relation-based database management system MySQL has been implemented. For the final recognized vital component, the streaming module, support for HTTP-based multimedia streams has been implemented. This choice of technique has been made due to the many benefits brought on by using HTTP, such as cost efficiency and bandwidth optimization. The use of HTTP is also currently a trending choice of technique Thesis for Master’s Degree at HIT and LiU within the streaming community due to the recently published standard MPEG-DASH.

This paper's aim is to design and implement a tool transforming REST Web APIs into APIs which facilitate the integration process. The improvement of integration is mainly divided into two parts: The embedding of semantic data in order to establish a common understanding of objects, properties and relations and the possibility to navigate through the API structure in an easy and automated way. The theoretical part is dealing with the fundamentals of Web APIs, today's related trends and the API's shortages and points of improvement. Another objective of this paper is to compare current data standards of output formats for so called Hypermedia APIs, whereas the most suitable components will be chosen as the output format of this paper's resulting tool. The practical part is dealing with the design and implementation of the tool being developed. Included, there is the description of test scenarios, related benefits for the tool's users as well as a final evaluation of the resulting tool and a discussion of the tool's future potential. The benefits of the tool are evaluated in a case study.

Natural disasters disrupt our daily life and cause many sufferings. Among the various natural disasters, flood is one of the most catastrophic. Assessing flood risk helps to take necessary precautions and can save human lives. The assessment of risk involves various factors which can not be measured with hundred percent certainty. Therefore, the present methods of flood risk assessment can not assess the risk of flooding accurately.  This research rigorously investigates various types of uncertainties associated with the flood risk factors. In addition, a comprehensive study of the present flood risk assessment approaches has been conducted. Belief Rule Base expert systems are widely used to handle various of types of uncertainties. Therefore, this research considers BRBES’s approach to develop an expert system to assess the risk of flooding. In addition, to facilitate the learning procedures of BRBES, an optimal learning algorithm has been proposed. The developed BRBES has been applied taking real world case study area, located at Cox’s Bazar, Bangladesh. The training data has been collected from the case study area to obtain the trained BRB and to develop the optimal learning model. The BRBES can generate different "What-If" scenarios which enables the analysis of flood risk of an area from various perspectives which makes the system robust and sustainable. This system is said to be intelligent as it has knowledge base, inference engine as well as the learning capability.

The Representational State Transfer (REST) architecture style surfaced quickly to be the favorable scheme to standardize the communication for network-based hypermedia systems due to its uniform discipline. As a result, various giant web services adopted the REST architecture as their primary architectural choice for their services. Regardless of the REST style's uniform discipline, de-facto practices appeared among REST services. Consequently, numerous studies have analyzed REST services and found to a significant extent, misalignments between the theoretical aspects of REST and the practices of REST. One of the studies examined a set of services that claimed to be REST against a class of 17 design criteria that realize the principles of the REST architecture, and it found that the majority of the subject services were inconsistent in applying the REST principles. This study has followed the research mentioned earlier and examined a limited set of REST services and surveyed REST practitioners to examine their practices against the same class of the 17 design criteria to determine to what extent they are applying the 17 design criteria and analyze the statistical differences between the practices of REST services and the practices of REST practitioners. The study results show that REST services and REST practitioners applied most of the 17 design criteria. However, the study also found heterogeneous practices in REST services that go against the principles of the REST style. Furthermore, the statistical analysis results suggest a misalignment between the practices of REST services and REST practitioners in relation to the 17 design criteria.

RESTful services are becoming increasingly popular. This work, that was carried out at Scania IT, investigates how a RESTful service should be designed and specified so that it meets the demands of an enterprise environment. In particular, this report will focus on documentation and validation of RESTful services, i.e. specifications. These are important aspects in an enterprise environment. The investigation consists of a comparative case study of four specification formats and Hypermedia As The Engine Of Application State (HATEOAS). The results show that the most commonly used specification formats have flaws. They also suggest that Swagger and RAML (RESTful API Modeling Language) are the two most mature formats. The results also show that HATEOAS, which is a more dynamic approach, can be useful in an enterprise environment but that it requires careful design. / REST-tjänster blir alltmer populära. Detta arbete, som utfördes på Scania IT, undersöker hur en REST-tjänst bör designas och specifieras för att möta de krav som finns i en enterprise-miljö. Specifikt kommer denna rapport att fokusera på dokumentation och validering av REST-tjänster, med andra ord specifikationer. Dessa är viktiga aspekter i en enterprise-miljö. Undersökningen består av en jämförande fallstudie med fyra specifikationsformat samt Hypermedia As The Engine Of Application State (HATEOAS). Resultaten visar att de mest vanligt förekommande specifikationsformaten har brister. De antyder också att Swagger och RAML (RESTful API Modeling Language) är de två mest mogna formaten. Resultaten visar också att HATEOAS, som är ett mer dynamiskt angreppssätt, kan vara användbart i en enterprise-miljö men att det kräver omsorgsfull design.

The utilization of Application Programming Interfaces (APIs) has experiencedsignificant growth due to the increasing number of applications being devel-oped. APIs serve as a means to transfer data between different applications.While RESTful has been the standard API since its emergence around 2000,it is now being challenged by Facebook’s GraphQL, which was introducedin 2015. This study aims to fill a knowledge gap in the existing literatureon API performance evaluation by extending the focus beyond read opera-tions to include CREATE, UPDATE, and DELETE operations in both REST-ful APIs and GraphQL. Previous studies have predominantly examined theperformance of read operations, but there is a need to comprehensively un-derstand the behavior and effectiveness of additional CRUD operations. Toaddress this gap, we conducted a series of controlled experiments and anal-yses to evaluate the response time and RAM utilization of RESTful APIsand GraphQL when executing CREATE, UPDATE, and DELETE operations.We tested various scenarios and performance metrics to gain insights into thestrengths and weaknesses of each approach. Our findings indicate that con-trary to our initial beliefs, there are no significant differences between the twoAPI technologies in terms of CREATE, UPDATE, and DELETE operations.However, RESTful did slightly outperform GraphQL in the majority of tests.We also observed that GraphQL’s inherent batching functionality resulted infaster response times and lower RAM usage throughout the tests. On the otherhand, RESTful, despite its simpler queries, exhibited faster response times inGET operations, consistent with related work. Lastly, our findings suggestthat RESTful uses slightly less RAM compared to GraphQL in the context ofCREATE, UPDATE, and DELETE operations.

Mobile money, a means of transferring payments via mobile devices, has become increasingly popular. The demand for convenient financial products or services is a crucial factor in why innovative developers want to incorporate mobile money into existing financial products/services. The goal is to provide convenient financial services that enable customers to quickly send and receive money between two mobile payment platforms. The Swedish blockchain company, Centiglobe, is searching for a system whereby payments can be made conveniently between two mobile payment platforms, specifically Alipay and M PESA. This thesis sought to develop such a system by utilizing the application programming interfaces (APIs) (provided by Alipay and M PESA) coupled with Centiglobe’s blockchain to facilitate payments between an Alipay user and an M PESA user. Solving this problem began with an initial literature study of previous work related to this topic and reading the extensive API documentation provided by Alipay and Daraja Safaricom (the developers of M PESA). Next, a flowchart was created and used as a guide throughout the development of the system. Testing the system entailed integration testing. The performance of the system was determined by measuring the execution time to make a cross system payment. A one-way transfer system was developed, as Alipay users can make a payment to M PESA users but not the reverse. The results of the integration testing shows that the system is a feasible solution. The execution time of a payment shows that it is relatively quick (~9.1 seconds); thus the performance is adequate.The conclusion is that this system is a viable solution for incorporating Alipay and M PESA as mobile payment services. Moreover, the system partially facilitates person-to-person payments between them – subject to the limitations of the Alipay API. In addition, this system provides a foundation for other inter-platform mobile payment solutions. / Mobila pengar, ett sätt att överföra betalningar via mobila enheter, har blivit alltmer populära. Efterfrågan på praktiska finansiella produkter eller tjänster är en avgörande faktor för varför innovativa utvecklare vill integrera mobila pengar i befintliga finansiella produkter / tjänster. Målet är att tillhandahålla praktiska finansiella tjänster som gör det möjligt för kunder att snabbt skicka och ta emot pengar mellan två mobila betalningsplattformar. Det svenska blockchainföretaget Centiglobe söker ett system där betalningar kan göras bekvämt mellan två mobila betalningsplattofrmar, särskilt Alipay och M-PESA. Denna avhandling försökte utveckla ett sådant system genom att använda applikationspogrammerinsgränssnitt (API) (tillhandahållet av Alipay och M-PESA) i kombination med Centiglobe’s blockchain för att underlätta betalningar mellan en Alipay-användare och en M-PESA-användare. Lösningen av detta problem började med en första litteraturstudie av tidigare arbeten relaterat till detta ämne samt en omfattande läsning av API-dokmentationen från Alipay och Daraja Safaricom (utvecklarna av M-PESA). Därefter skapades ett flödesschema och detta användes som en guide under hela utvecklingen av systemet. Testning av systemet medförde integrationstestning. Systemets prestanda bestämdes genom att mäta exekveringstiden för att göra ett tvärsystemsbetalning. Ett envägsöverföringssystem utvecklades, eftersom Alipay-användare kan göra en betalning till M-PESA-användare men inte tvärtom. Resultaten av integrationstestningen visar att systemet är en genomförbar lösning. Utbetalningstiden för en betalning visar att den är relativt snabb (~9.1 sekunder); därav en lagom prestanda. Slutsatsen är att detta system är en lönsam lösning för att integrera Alipay och M-PESA som mobila betalningstjänster. Dessutom underlättar systemet delvis personliga betalningar mellan dem – med förbehåll för begräsningarna i Alipay API. Dessutom erbjuder detta system en grund för andra mobila betalningslösningar mellan plattformarna.

Amaethon is a web application that is designed for enterprise farm management. It takes a job typically performed with spreadsheets, paper, or custom software and puts it on the web. Farm administration personnel may use it to schedule farm operations and manage their resources and equipment. A survey was con- ducted to assess Amaethon’s user interface design. Participants in the survey were two groups of students and a small group of agriculture professionals. Among other results, the survey indicated that a calendar interface inside Amaethon was preferred, and statistically no less effective, than a map interface. This is despite the fact that a map interface was viewed by some users as a potentially important and effective component of Amaethon.

Yes / Interoperability within different healthcare systems (clinics/hospitals/pharmacies) remains an issue of further research due to a barrier in sharing of the patient’s Electronic Health Record (EHR) information. To solve this problem, cross healthcare system collaboration is required. This paper proposes an interoperability framework that enables a pharmacist to access an electronic version of the patient’s prescription from the doctor using a RESTFul API with ease. Semantic technology standards like Web Ontology Language (OWL), RDF (Resource Description Framework) and SPARQL (SPARQL Protocol and RDF Query Language) were used to implement the framework using JENA semantic framework tool to demonstrate how interoperability is achieved between a pharmacy and a clinic JENA was used to generate the ontology models for the pharmacy called pharmacy.rdf and clinic called clinic.rdf. The two models contain all the information from the two isolated systems. The JENA reasoner was used to merge the two ontology models into a single model.rdf file for easy querying with SPARQL. The model.rdf file was uploaded into a triple store database created using FUSEKI server. SPARQL Endpoint generated from FUSEKI was used to query the triple store database using a RESTFul API. The system was able to query the triple store database and output the results containing the prescription name and its details in JSON and XML formats which can be read by both machines and humans. / Supported by a Institutional Links grant, ID 261865161, under the Newton-Ristekdikti Fund partnership. The grant is funded by the UK Department for Business, Energy and Industrial Strategy and Indonesia Ministry of Research, Technology and Higher Education and delivered by the British Council.

Résumé : Les services Web, issus de l’avancée technologique dans le domaine des réseaux informatiques et des dispositifs de télécommunications portables et fixes, occupent une place primordiale dans la vie quotidienne des gens. La demande croissante sur des services Web multimédia (SWM), en particulier, augmente la charge sur les réseaux d’Internet, les fournisseurs de services et les serveurs Web. Cette charge est essentiellement due au fait que les SWM de haute qualité nécessitent des débits de transfert et des tailles de paquets importants. La qualité de service (par définition, telle que vue par l’utilisateur) est influencée par plusieurs facteurs de performance, comme le temps de traitement, le délai de propagation, le temps de réponse, la résolution d’images et l’efficacité de compression. Le travail décrit dans cette thèse est motivé par la demande continuellement croissante de nouveaux SWM et le besoin de maintenir et d’améliorer la qualité de ces services. Nous nous intéressons tout d’abord à la qualité de services (QdS) des SWM lorsqu’ils sont mis en œuvre sur des ordinateurs, tels que les ordinateurs de bureau ou les portables. Nous commençons par étudier les aspects de compatibilité afin d’obtenir des SWM fonctionnant de manière satisfaisante sur différentes plate-formes. Nous étudions ensuite la QdS des SWM lorsqu’ils sont mis en œuvre selon deux approches différentes, soit le protocole SOAP et le style RESTful. Nous étudions plus particulièrement le taux de compression qui est un des facteurs influençant la QdS. Après avoir considéré sous différents angles les SWM avec mise en œuvre sur des ordinateurs, nous nous intéressons à la QdS des SWM lorsqu’ils sont mis en œuvre sur FPGA. Nous effectuons alors une étude et une mise en œuvre qui permet d’identifier les avantages à mettre en œuvre des SWM sur FPGA. Les contributions se définissent en cinq volets comme suit : 1. Nous introduisons des méthodes de création, c’est-à-dire conception et mise en œuvre, de SWM sur des plate-formes logicielles hétérogènes dans différents environnements tels que Windows, OS X et Solaris. Un objectif que nous visons est de proposer une approche permettant d’ajouter de nouveaux SWM tout en garantissant la compatibilité entre les plate-formes, dans le sens où nous identifions les options nous permettant d’offrir un ensemble riche et varié de SWM pouvant fonctionner sur les différentes plate-formes. 2. Nous identifions une liste de paramètres pertinents influençant la QdS des SWM mis en œuvre selon le protocole SOAP et selon le style REST. 3. Nous développons un environnement d’analyse pour quantifier les impacts de chaque paramètre identifié sur la QdS de SWM. Pour cela, nous considérons les SWM mis en œuvre selon le protocole SOAP et aussi selon style REST. Les QdS obtenues avec SOAP et REST sont comparées objectivement. Pour faciliter la comparaison, la même gamme d’images (dans l’analyse de SWM SOAP) a été réutilisée et les mêmes plate-formes logicielles. 4. Nous développons une procédure d’analyse qui permet de déterminer une corrélation entre la dimension d’une image et le taux de compression adéquat. Les résultats obtenus confirment cette contribution propre à cette thèse qui confirme que le taux de compression peut être optimisé lorsque les dimensions de l’image ont la propriété suivante : le rapport entre la longueur et la largeur est égal au nombre d’or connu dans la nature. Trois libraires ont été utilisées à savoir JPEG, JPEG2000 et DjVu. 5. Dans un volet complémentaire aux quatre volets précédents, qui concernent les SWM sur ordinateurs, nous étudions ainsi la conception et la mise en œuvre de SWM sur FPGA. Nous justifions l’option de FPGA en identifiant ses avantages par rapport à deux autres options : ordinateurs et ASICs. Afin de confirmer plusieurs avantages identifiés, un SWM de QdS élevée et de haute performance est créé sur FPGA, en utilisant des outils de conception gratuits, du code ouvert (open-source) et une méthode fondée uniquement sur HDL. Notre approche facilitera l’ajout d’autres modules de gestions et d’orchestration de SWM. 6. La mise à jour et l’adaptation du code open-source et de la documentation du module Ethernet IP Core pour la communication entre le FPGA et le port Ethernet sur la carte Nexys3. Ceci a pour effet de faciliter la mise en œuvre de SWM sur la carte Nexys3. // Abstract : Web services, which are the outcome of the technological advancements in IT networks and hand-held mobile devices for telecommunications, occupy an important role in our daily life. The increasing demand on multimedia Web services (MWS), in particular, augments the load on the Internet, on service providers and Web servers. This load is mainly due to the fact that the high-quality multimedia Web services necessitate high data transfer rates and considerable payload sizes. The quality of service (QoS, by definition as it is perceived by the user) is influenced by several factors, such as processing time, propagation delay, response time, image resolution and compression efficacy. The research work in this thesis is motivated by the persistent demand on new MWS, and the need to maintain and improve the QoS. Firstly, we focus on the QoS of MWS when they are implemented on desktop and laptop computers. We start with studying the compatibility aspects in order to obtain MWS functioning satisfactorily on different platforms. Secondly, we study the QoS for MWS implemented according to the SOAP protocol and the RESTful style. In particular, we study the compression rate, which is one of the pertinent factors influencing the QoS. Thirdly, after the study of MWS when implemented on computers, we proceed with the study of QoS of MWS when implemented on hardware, in particular on FPGAs. We achieved thus comprehensive study and implementations that show and compare the advantages of MWS on FPGAs. The contributions of this thesis can be resumed as follows: 1. We introduce methods of design and implementation of MWS on heterogeneous platforms, such as Windows, OS X and Solaris. One of our objectives is to propose an approach that facilitates the integration of new MWS while assuring the compatibility amongst involved platforms. This means that we identify the options that enable offering a set of rich and various MWS that can run on different platforms. 2. We determine a list of relevant parameters that influence the QoS of MWS. 3. We build an analysis environment that quantifies the impact of each parameter on the QoS of MWS implemented on both SOAP protocol and RESTful style. Both QoS for SOAP and REST are objectively compared. The analysis has been held on a large scale of different images, which produces a realistic point of view describing the behaviour of real MWS. 4. We develop an analysis procedure to determine the correlation between the aspect ratio of an image and its compression ratio. Our results confirm that the compression ratio can be improved and optimised when the aspect ratio of iiiiv an image is close to the golden ratio, which exists in nature. Three libraries of compression schemes have been used, namely: JPEG, JPEG2000 and DjVu. 5. Complementary to the four contributions mentioned above, which concern the MWS on computers, we study also the design and implementation of MWS on FPGA. This is justified by the numerous advantages that are offered by FPGAs, compared to the other technologies such as computers and ASICs. In order to highlight the advantages of implementing MWS on FPGA, we developed on FPGA a MWS of high performance and high level of QoS. To achieve our goal, we utilised freely available design utilities, open-source code and a method based only on HDL. This approach is adequate for future extensions and add-on modules for MWS orchestration.