An Introduction to Search Engines and Web Navigation

Chapter 9. SOCIAL NETWORKS

"The internet is becoming the town square for the global village of tomorrow."

—Bill Gates, Cofounder of Microsoft

Social networks bring another dimension to the Web by considering the links between people and emerging communities, in addition to the links between web pages. Social network analysis is having a major impact on search and navigation technologies in ways which were hard to predict a few years ago. Technologies such as peer-to-peer networks, collaborative filtering, and weblogs (known as blogs) are examples of social software, utilizing the way in which web users interact with each other and with the web in order to add value to existing information seeking methods.

CHAPTER OBJECTIVES

• Introduce the concept of a social network.

• Describe Milgram's small-world experiment and a recent counterpart experiment using e-mail, rather than post, to forward messages.

• Introduce the concepts of a collaboration graph and the Erdös number.

• Show how social networks can be extracted from the Web.

• Give an account of some of the social network start-ups.

• Introduce the basic terminology used in social network analysis.

• Show how web communities can be identified.

• Introduce the three different types of peer-to-peer (P2P) networks: centralized, decentralized, and hybrid.

• Describe the method of distributed hash files to locate content in P2P networks.

• Introduce the BitTorrent file distribution system.

• Introduce JXTA P2P search.

• Discuss incentives in P2P systems to deal with the ...