Mobile Data ManagementMobile Data ManagementKen RimeyKen Rimey

2003-2004:

• Personal Distributed Information Store (PDIS)

2005-:

• Too Many Boxes - end-user digital asset management for networked consumer electronic devices.

• µXMLDB - an XML database for mobile devices.

PDISPDIS (2003-2004) (2003-2004)

• Next-generation data synchronization: Enable people to store copies of their data on several devices, and several computers, and to keep these copies in sync.

• State-transfer, update-anywhere replicated XML database.

– PIM data.

– Digital media metadata.

• Ported to Nokia’s Python for Series 60.

TMB: Too Many BoxesTMB: Too Many Boxes

• Ken Rimey, HIIT

• How will consumers manage their files on multiple handheld devices, computers, and home/car entertainment boxes?

• How to combine control with simplicity, rejecting both complete automation and complex graphical user interfaces?

• Utilize PDIS/PDOS results to build a home network testbed.

• 2005 volume: 4-5 person-years

Hypothesized IssuesHypothesized Issues

• WHERE to store copies of files?

• WHEN to synchronize them over wireless networks?

• WHOse personal devices should have access?

TMB MethodologyTMB Methodology

• Build and study three prototypes:

– Start with raw sharing of files among several phones and several computers, presumed to belong to the same person (1H2005).

– Then add in multiple people (family members, etc.), end-user configurability, a focus on specific media types, a mockup of a home entertainment system, and some experimentation with gestural or multimodal interaction techniques (-2006).

– Finally, capitalize on this infrastructure by integrating additional applications or devices, or by adapting it to some other setting besides the home (2007).

µXMLDB: µXMLDB: An XML Database for An XML Database for Mobile DevicesMobile Devices

• Kenneth Oksanen, HUT and HIIT

• XML is of increasing interest as a vendor-neutral exchange and storage format in handheld devices.

• Existing XML database solutions target large, administered servers and mostly text-oriented XML data.

• Needed: A self-administering XML database with small memory and flash consumption, a simple vendor-neutral index creation API, and extensions for querying data-oriented XML.

• 2005 volume: 3 person-years

Research TopicsResearch Topics

• Index management

• Query language

• Representation of stored XML

Index ManagementIndex Management

• Indexing of XML is not well understood.

– Some systems build large generic indices.

– Others allow specifying more accurate indices, but no standard API exists for this.

• Specify intuitively with query templates:

/todo[date="%s"]

• Or automatically based on queries:

/todo[date="20040922"]

/todo[date="20040923"]

• The latter leads to an opportunity to construct very concise and selective indices.

Query LanguageQuery Language

• Based on XPath and possibly XQuery.

• Extended for, among other things, categories:

– The query /todo[isa(@category, "work")] matches the document <todo category="PDIS">...</todo>,if “PDIS” is defined as being work.

– Categories change, and we don't want to reindex the whole database when they do.

• Handling RDF and OWL is a possible further research issue.

Representation of Stored XMLRepresentation of Stored XML

• Allow use of compression.

• Store big CDATA blobs separately.

µXMLDB DeliverablesµXMLDB Deliverables

• An open-source C implementation for Unix and Symbian OS.

• SWIG interface supporting other languages.

• Use existing system software (Berkeley DB, SQL, …) for persistence, storage and indexing.