Mobile Search

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Mobile Search Social Network Search Using
Mobile Devices1st IEEE International
Peer-to-Peer for Handheld Devices WorkshopIEEE
CCNC, Las Vegas, 12th of January 2007

• Mikko Vapa, research student, mikko.vapa_at_jyu.fi
• With co-authors Pedro Tiago, Niko Kotilainen,
  Heikki Kokkinen and Jukka K. Nurminen (Nokia P2P
  Team)
• Department of Mathematical Information Technology
• University of Jyväskylä, Finland
• www.mit.jyu.fi/cheesefactory

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Background

• Mobile phones' computational power has been
  improving approaching the capabilities of general
  purpose computers
• Nowadays it is possible to host a web site on a
  mobile device
• It is also expected that the number of mobile web
  sites will outnumber the static web servers
• Recently, there has been a growing interest in
  how to explore the mobile phone capabilities in
  the web search context and how to merge them with
  existing phone functionalitiesJohan Wikman,
  Ferenc Dosa, and Mikko Tarkiainen. Personal
  website on a mobile phone. Technical report,
  Nokia Research Center, 2006

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Mobile Search

• Mobile Search is a system for social network
  search on a mobile device
• Prototype was implemented on top of Drupal
  content management system running on Mobile
  Apache/Raccoon mobile web server
• Based on pure peer-to-peer architecture offers
  scalability, efficiency, resilience to failures
  and privacy at a higher degree than centralized
  solutionsChoon-Hoong, Nutanong and Buyya,
  Peer-to-Peer Networks for Content Sharing,
  Peer-to-Peer Computing Evolution of a Disruptive
  Technology, 2005

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Features

• Allows executing searches to the contents of
  mobile devices using a web interface
• Searches through social network defined by the
  addressbooks of the mobile devices
• Manages access rights for different kind of
  contents (calendar data, photos, blogs etc.)
  using mottoI only display what I want to who I
  want
• Can also search normal Drupal websites

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New Search Concepts

• Manual multi-hopping
• Users search one graph level of their social
  network at a time usually starting from their
  neighbors
• Every time a user issues a search query the
  mobile device forwards it to all the neighbors of
  the user
• The neighbors answer back by returning a result
  set and a list of their neighbors
• If the user who issued the query is not satisfied
  by the results he can always ask new results from
  the next level neighbors as long as there are
  non-visited nodes in the network
• Automatic multi-hopping
• A sorting algorithm decides which of the
  non-visited nodes are queried further thus
  avoiding the need for user decision
• Automatically sorting the non-visited nodes leads
  to tradeoff between search accuracy and easiness
  of searching suggesting that both manual and
  automatic multi-hopping should be available for
  the user

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Benefits

• Compared to centralized web search engines
• Mobile Search provides access to rare personal
  data relevant to people close in the social
  network
• The contents indexed by Mobile Search might not
  be referenced anywhere but still they are
  searchable
• Real-time - Does not provide outdated links
• Highly distributed, decentralized and no single
  point of failure
• Mobile Search can utilize websites internal
  search functionalities
• Search is executed within the limits of access
  control rights providing means to search
  non-public data (internal search among friends
  etc.)
• However, social network search is not suited to
  find popular content
• But, it's a powerful mechanism in restricted
  topic set environmentMislove, Gummadi, and
  Druschel, Exploiting social networks for internet
  search, Proceedings of the 5th Workshop on Hot
  Topics in Networks, 2006

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Drupal Prototype of Mobile Search

• Drupal is an open-source content management
  system for managing and publishing several types
  of content
• Prototype is logically divided to local web
  search engine and metacrawler parts
• Local web search engine is a search service,
  which manages the search index of the mobile
  device
• Metacrawler is a search service, which uses other
  local web search engines for getting the results
  and combines different result sets into one
• Metacrawler was built as a weakly coupled
  component on top of Drupal local web search
  engine
• Features automatic multi-hopping and result
  interleaving
• Differs from blog aggregators because content is
  being searched and a set of queried nodes is not
  fixed

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Drupal Prototype of Mobile Search

• Drupal tac_lite module and Drupal module were
  used as fundamental elements in the prototype
• These modules allow setting content access rules
  and to process user authentication in distributed
  fashion without any central servers
• An extra component that allows to do queries to
  local mobile phone content such as location,
  address book and meeting data was implemented
• This feature was built as a simple proof of
  concept
• However, the prototype is also able to gather
  search results from unmodified Drupal web sites

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User Interface
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Technical Limitations

• The current implementation is single threaded
  because Mobile Apache/Raccoon web server doesn't
  support multiple threadsWikman, Mobile web
  server - eurooscon presentation, 2006Wikman
  and Dosa, Providing http access to web servers
  running on mobile phones, Technical report, Nokia
  Research Center, 2006
• Single-threaded nature of the metacrawler is a
  drawback
• This has a negative impact on response time
  because site crawling is done in a serial way
• A multi-threaded implementation would speed up
  the system considerably

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Future Work

• Query forwarding/node sorting algorithms should
  be considered though in a different setting than
  previous studies
• Algorithms like K-Random walk, Expanding Ring and
  hybrids using NeuroSearch neural network should
  be considered
• Requires collecting some search usage statistics
• Also one interest is the usability of search
  results, and new paradigms of displaying
  different types of information and user
  interaction
• Web 2.0 may not be fully suitable for mobile
  device paradigm of interaction
• This could also be an excellent opportunity to
  use a query language applied to this type of
  systems for example an adaptation of
  webSQLMendelzon et al., Querying the world wide
  web, Int. J. on Digital Libraries, 1997
• Would likely create a bigger interoperability and
  homogenization in this type of systems with
  easier deployment of new functionalities

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Future Work

• Mobile Search can be extended by creating
  different ways of accessing the content, one
  entry point could be tags
• Tags work as links between content categorized
  similarly
• At each hop the user gets the list of contents
  tagged in a similar way by nodes in its
  neighborhood
• SearchingPortugal would give six results,but
  then theuser might continue thesearch via
  Lisboa tag andfinds theTrolley image

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Conclusions

• Mobile Search complements traditional web search
  engines
• It gives the user means to explore the neighbors
  contents by traveling to the friends network
  topology
• It covers a multitude of environments not covered
  by the centralized solutions
• One of the main advantages in relation to current
  centralized social network sites is the
  possibility to manage the site without
  interference from an external entity
• Currently in a normal social network site a user
  can only display or use modules made available by
  a third entity
• With Mobile Search approach it is possible to
  merge different social network sites that cover
  different topics and create a social network
  "melting pot