mobile search presentation

UNIVERSITY OF JYVÄSKYLÄ

Mobile Search – Social Network Search Using Mobile Devices

1st IEEE International Peer-to-Peer for Handheld Devices WorkshopIEEE CCNC, Las Vegas, 12th of January 2007

Mikko Vapa, research student, [email protected] co-authors Pedro Tiago, Niko Kotilainen,

Heikki Kokkinen and Jukka K. Nurminen (Nokia P2P Team)

Department of Mathematical Information TechnologyUniversity of Jyväskylä, Finland

www.mit.jyu.fi/cheesefactory


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 functionalities

[Johan Wikman, Ferenc Dosa, and Mikko Tarkiainen. Personal website on a mobile phone. Technical report, Nokia Research Center, 2006]


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 solutions[Choon-Hoong, Nutanong and Buyya, Peer-to-Peer Networks for Content Sharing, Peer-to-Peer Computing: Evolution of a Disruptive Technology, 2005]


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 motto:“I only display what I want to who I want”

• Can also search normal Drupal websites


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


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 environment[Mislove, Gummadi, and Druschel, Exploiting social networks for internet search, Proceedings of the 5th Workshop on Hot Topics in Networks, 2006]


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


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


User Interface


Technical Limitations

• The current implementation is single threaded because Mobile Apache/Raccoon web server doesn't support multiple threads[Wikman, Mobile web server - eurooscon presentation, 2006][Wikman 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


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 webSQL[Mendelzon 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


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• Searching

Portugal would give six results,but then theuser might continue thesearch via Lisboa tag andfinds theTrolley image


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”