FACULTY OF SCIENCE AND TECHNOLOGY DEPARTMENT OF COMPUTER SCIENCE Javza A runtime supporting dynamic app configuration and integration in asymmetric systems Anders Tungeland Gjerdrum INF-3981 Master's Thesis in Computer Science July, 2012 ii Abstract The advent of cloud computing alongside with pervasive form factors such as smart devices, introduces a new meaning to asymmetric system models. These new clients act as a presentational layer alleviating much of the computational and storage concerns to cloud services. The application platforms associated with these creates new opportunities for third party developers to provide domain specific applications (apps) to smart devices. Restricted interaction surfaces on smart device introduce new challenges to how apps are managed on these. Moreover, for security purposes as well as strict resource requirements, apps running in these environments are commonly subject to very strict isolation. We conjure that there are benefits with allowing automatic configuration apps onto a client system. Furthermore, we suggest that integration between apps residing at the same host, as well as different hosts, is beneficial to system functionality. By enabling this we could alleviate much of the interaction necessary for users and reduce the time consumed in using such smart devices. The concrete asymmetric system explored in this thesis is the Windows 8 app platform. This platform poses several hindrances to our conjecture. For security reasons, automatic configuration of apps onto a client system is prohibited. Apps run inside a sandboxed environment where they are isolated from the system and other apps. Access to resources is prohibited unless explicitly allowed by the user. As a consequence, communication between apps is forbidden. This is further complicated by the fact that apps in this environment are suspended when not in use. This thesis introduces Javza, a runtime to support dynamic app configuration and integration in Windows 8. Javza provides support for automatic installment of apps based on simplified contextual information. Furthermore, it provides app integration by allowing apps to share data, both within the same and across different systems. We present and evaluate the associated performance costs of deploying Javza inside a Windows 8 environment. We further evaluate the applicability of Javza by implementing a specific use case involving collaborative search. Lastly we discuss some of the security implications associated with our design, and some future improvements in Windows 8 to support our conjecture. iii iv Acknowledgements I would like to thank my advisor Prof. Dag Johansen for all your guidance and support. Your enthusiasm is highly infectious. I would also like to extend my gratitude towards my co‐advisor Krister Mikalsen, your perspective and insight has been much appreciated. Further, I would like to thank my Girlfriend for listening to my mad rambles these last 5 months. Your compassion knows no boundary, I love you. I would like to thank Robert Pettersen for his valued friendship and helpful discussions in the last five years. I would like to thank my family, especially my mother and father, for being true sources of inspiration. Lastly, I would like to thank my fellow colleagues at the IAD research lab, including Audun Nordahl, Åge Kvalnes and Dr. Håvard D. Johansen for their insight and help throughout this process. v vi Table of Figures Figure 1: Application platform model ................................................................................................................. 7 Figure 2: The Android Operating System Architecture ......................................................................................... 9 Figure 3: Metro Immersive User Interface ......................................................................................................... 11 Figure 4: Windows 8 Architecture [10] ............................................................................................................... 14 Figure 5: Windows Runtime Object Projections [10] .......................................................................................... 15 Figure 6: App Lifecycle state diagram ................................................................................................................ 16 Figure 7: Windows Push Notification Service [15] .............................................................................................. 18 Figure 8: Architectural Overview ....................................................................................................................... 22 Figure 9: App Provider interaction ..................................................................................................................... 24 Figure 10: Group Recommendation Service ....................................................................................................... 25 Figure 11: Arbitrator placement in architecture ................................................................................................. 26 Figure 12: Architecture in use case .................................................................................................................... 27 Figure 13: Data Base Schema ............................................................................................................................. 33 Figure 14: 3‐Dimensional terms ......................................................................................................................... 36 Figure 15: App Management Component .......................................................................................................... 39 Figure 16: Communication ................................................................................................................................ 40 Figure 17: Abstract functionality ....................................................................................................................... 40 Figure 18: Centralized Approach ........................................................................................................................ 42 Figure 19: Peer‐to‐peer organization ................................................................................................................. 44 Figure 20: Disk Based IPC ................................................................................................................................... 48 Figure 21: Desktop side and App Side interaction .............................................................................................. 50 Figure 22: App Side Internals ............................................................................................................................. 51 Figure 23: Arbitrator Data Flow ......................................................................................................................... 55 Figure 24: Named Pipes Data Flow .................................................................................................................... 56 Figure 25: IPC Throughput ................................................................................................................................. 57 Figure 26: IPC Round‐Trip time .......................................................................................................................... 59 Figure 27: Inter‐Host Arbitrator Data Flow ......................................................................................................... 61 Figure 28: Inter‐Host TCP Data Flow .................................................................................................................. 61 Figure 29: Inter‐Host Throughput ...................................................................................................................... 62 Figure 30: Inter‐Host Round‐Trip Time ............................................................................................................... 63 Figure 31: Idle Runtime overhead (Total KB/s of I/O) ......................................................................................... 65 Figure 32: Time taken to install apps ................................................................................................................. 67 Figure 33: Case study usage ............................................................................................................................... 73 Figure 34: 5 dynamically configured apps displayed on the start screen ............................................................. 75 Figure 35: A section of the group Interaction GUI inside a single app ................................................................. 75 vii viii Table of Content Abstract ........................................................................................................................................... iii Acknowledgements .......................................................................................................................... v Table of Figures .............................................................................................................................. vii Table of Content ............................................................................................................................. ix List of Acronyms ............................................................................................................................. xii 1 Introduction ............................................................................................................................