T-07S-05

Distributed Filesystem for Wireless Mesh Networks

Assigned to: Felix Bechstein

Advisor: Anatolij Zubow

Expected Submission: December 2007

Problem Statement

• Which problem do you want to solve?
  • There is no filesystem only based on DHT for decentralized use, like our BRN.
• To which domain of Computer Science does this problem relate to?
• Why is the problem interesting? Why is it difficult?
  • A filesystem is a basic service for many applications on top. It can be used for class- and update-distribution, backup- or storage-service and many more.

Deliverables

• At the end of the project, what will you have delivered?
  • A basic distributed (high-performance) filesystem, using only the DHT.
  • An interface to that filesystem in fuse or nfs, to mount it.
• What does it mean that the project was successful?
  • The filesystem's performance is sufficient for class- or upgrade-distribution.

Prior Art

• Who are your competitors? What are they doing?
• How is your work different?
• List of publications related to your topic.

Key Ideas / Project Execution Plan

• How will you approach the problem?
  • I'll build the filesystem from bottom to top:
    • abstraction to fuse, nfs or similar
    • fs-layer: c# library, with an ioctl-like interface
    • block-layer: abstract the dht to simple blocks/extends variable in size
    • dht-layer: use the DHT
  • All the BRN-magic is done in the DHT, so i'll try to build a clever block structure with some caching to improve everything's speed.
• On which contributions of others do you depend on?
  • Distributed Hash Table by Anselm Ringleben

Project Log

• What you have done so far?
  • Define some Interfaces (not fixed yet).
  • Implement a DHT interface localy (not distributed).
  • Implement the Blocklayer.
    • hardcopys on blocklayer
  • Implement Direcorys:
    • openDir
    • mkdir
    • rmdir
    • ls
    • close
    • chdir
    • pwd
  • Implement Files
    • openFile
    • unlink
    • read
    • write
    • truncate
    • close
  • Implement Fuse Frontend
  • first prototype
• What You plan to do next?
  • fix bugs
  • push performance to its limits