(rev. 01/01/2010)
Notes On Chapter Two
-- Internet Trends
Chapter Two: Internet Trends
- 2.1 Introduction
- change to networking and Internet
- Internet motivation: centralized to distributed
- Internet applications
- communication paradigms
- programming interface
- 2.2 Resource Sharing
- The purpose of early forms of computer networks was connect multiple
users to a single large computer.
- People want networks so they can share printers, share files, share
powerful CPU's.
- At the time that the Internet got its start, the sharing of powerful
computers was important to researchers working at government
laboratories. Computers were expensive and sharing was seen as a
way to save money.
- The Department of Defense is also said to have been interested in
developing a network that could continue to function even after
being heavily damaged.
- ARPA put together a large group of the best and brightest
individuals available and they created the Internet. The story
has something of the flavor of the story of the Manhattan
project.
- ARPANET was developed all through the 70's and 80's. It became
known as the Internet. MILNET split off and the Internet was run
by NSF for a while. It became commercialized in the 90's.
- 2.3 Growth of the Internet
- Plots show that the number of hosts (computers) on the Internet
approximately doubled every 9-14 months from 1981 through 2008.
- What has been the relative growth in various areas of the world?
- 2.4 From Resource Sharing to Communication
- Now that computing equipment is cheap and powerful, the original
emphasis on resource sharing has shifted.
- The sharing of information (communication) is now much more
important that the sharing of hardware.
- 2.5 From Text to Multimedia
- Early on, most of the data on the Internet was text. Today much of
it is high-fidelity audio and high-resolution video.
- 2.6 Recent Trends
- Telephone: Voice over IP (VoIP)
- Cable Television: Switch to digital and IP delivery
- Cellular: Switch from analog to digital (3G)
- Internet Access: Switch from wired to wireless (Wi-Fi)
- Data Access: Switch from centralized to distributed (P2P)
- High-Quality Teleconferencing
- Navigation Systems
- Sensor Networks
- Social Networking