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An Online Analytical Processing (OLAP) cube is a way to represent a multidimensional database. The multidimensional database often uses a star schema and populates it with the data from a relational database. The purpose of using an OLAP cube is usually to find valuable insights in the data like trends or unexpected data and is therefore often used within Business intelligence (BI). Mondrian is a tool that handles OLAP cubes that uses the query language MultiDimensional eXpressions (MDX) and translates it to SQL queries. Apache Kylin is an engine that can be used with Apache Hadoop to create and query OLAP cubes with an SQL interface. This thesis investigates whether the engine Apache Spark running on a Hadoop cluster is suitable for analysing OLAP cubes and what performance that can be expected. The Star Schema Benchmark (SSB) has been used to provide Ad-Hoc queries and to create a large database containing over 1.2 billion rows. This database was created in a cluster in the Omicron office consisting of five worker nodes and one master node. Queries were then sent to the database using Mondrian integrated into the BI platform Pentaho. Amazon Web Services (AWS) has also been used to create clusters with 3, 6 and 15 slaves to see how the performance scales. Creating a cube in Apache Kylin on the Omicron cluster was also tried, but was not possible due to the cluster running out of memory. The results show that it took between 8.2 to 11.9 minutes to run the MDX queries on the Omicron cluster. On both the Omicron cluster and the AWS cluster, the SQL queries ran faster than the MDX queries. The AWS cluster ran the queries faster than the Omicron cluster, even though fewer nodes were used. It was also noted that the AWS cluster did not scale linearly, neither for the MDX nor the SQL queries.

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Passwords are the most commonly used form of authentication. The game based password system is a new concept based on a graphical password but with game features. This research focuses on the authentication systems’ usability and acceptability, from the users’ point of view. This research will investigate if users would rather use a game based password or the dominating alphanumeric password system, and how the users experience the security of the game based password. The game based password prototype used in this study is a simplified replication of the Game Changer Password by McLennan and co-workers. The present study consisted of a usability test with questionnaire and interviews. The results from the usability test show that the game based password is easier to remember than an alphanumeric password. The conclusion of the study is mainly that the game based password is both a secure and usable authentication method. / Lösenord är den mest använda formen av autentisering. ”The game based password system”, är ett nytt koncept som är baserat på ett grafiskt lösenord men med spelfunktioner. Denna forskning fokuserar på autentiseringsystemets användarvänlighet och acceptabilitet, från användarens synvinkel. Denna forskning kommer att undersöka om användare hellre använder ett ”game based password” istället för ett alfanumeriskt lösenord, och hur användaren uppfattar säkerheten av ”the game based password”. Spelplanen i denna studie utgörs av en förenklad variant av ”the Game Changer Password system” av McLennan med medarbetare. Jämförelsen i denna uppsats är baserad på ett användartest med enkät och intervjuer. Resultatet från användartestet visar att ”the game based password” är lättare att komma ihåg än ett alfanumeriskt lösenord. Slutsatserna av denna studie är huvudsakligen att ”the game based password” är både en säker och användbar autentiserings metod.