Computers And Information Super-Highway

Xiannong Meng
Department of Computer Science
The University of Texas - Pan American
Edinburg, TX 78539-2999
meng@panam.edu

Spring 1998

Outline of the Presentation

• Origin and a brief history of the Internet
• Components of the Internet
• Information Super-Highway
• Current status of the Internet
• Further probes

Origin And A Brief History of the Internet

• In 1968, the U.S. Defense Advanced Research Projects Agency (DARPA) initiated the effort to develop a technology now known as packet switching.
• In 1969 a four-node experimental computer network connecting UCLA, UCSB, SRI and the University of Utah, using Interface Message Processors (computers dedicated to message passing). This network was called ARPANET.
• In three years (1969-1972), the ARPANET grew to about 40 nodes.
• DARPA developed packet radio network and packet satellite network in early 1970s; XEROX developed the Ethernet local area network based on coaxial cable in mid-1970s.
• Need for inter-network arises.
• TCP/IP, the most important protocols in the Internet, was designed and developed in mid to late 1970.
• January 1983, the Defense Communications Agency declared TCP/IP the standard for ARPANET.

• By 1990, the ARPANET had been overtaken by newer networks such as NSFNET. A large number of regional networks were developed.
• Internet was needed for all networks to communicate to each other. The Internet started to take shape around mid-1980s.
• The number of hosts on the Internet was estimated at 16 millions by January 1997

Components of the Internet

• Hardware:
  • Hosts (computers)
  • Network interface card
  • Communication medium (twisted pairs, co-axial cable, fiber optics, microwave etc.)
  • Routers
  • Common carriers
• Software: a layered structure
• People:
  • users
  • service providers (universities, companies, commercial ISPs)
  • network providers (telephone companies, network companies etc.)

Information Super-Highway

• Internet forms a set of inter-connected networks which connects to millions of hosts.
• Computers on the Internet are organized into hierarchies
  • At the top level domains: *.edu, *.com, *.org, *.gov, *.net, *.us, *.fr, *.cn, *.mx ...
  • Within each of these top level domain: *.panam.edu, *.utsa.edu, *.ibm.com, *.sony.com, *.cnd.org, *.whitehouse.gov. Typically each individual organization is at this level.
  • The next level can be department, or individual computers. Every computer on the Internet has to have a unique address.
• IP addresses (license plates for vehicles): IP addresses are represented in four integers, each is between 0 and 255, e.g. 129.113.132.225 where 129.113.* is the IP address set for UT Pan American.
• IP addresses and the name of the computer on the Internet are translated by Domain Name Systems (DNS).
• How many computers can we have before running out IPs? About four billions.

• Users can travel (surf) around the Internet and access information.
• How fast can we go?
  • Bits and bytes travel at the speed of the light
  • Computers need time to process the information (generated and received)
  • Network interface card need time to transmit the information (locally: Ethernet, backbone: ATM)
  • When multiple computers send information at the same time, collisions happen, have to be resolved.
  • When messages go to the routers they have to wait if other messages are in transition
• The rules that govern the operation of the Internet are called protocols.
• The types of traffic (types of vehicles) on the Internet: multimedia, i.e. text, audio, video.
• The types of information available on the Internet:
  • Education, research
  • Entertainment
  • Tourist and travel
  • Commercial, shopping
  • Information about people, about organization
  • Others

Current Status

According to Tony Rutkowski of General Magic (as of Jan 1997)

(www.genmagic.com/Internet/Trends)

• A total of 16 million hosts on the Internet
• *.com has about 4 million hosts
• *.edu has about 2.6 million hosts
• *.net has about 1.5 million hosts
• *.mil has about 0.7 million hosts
• *.gov has about 0.4 million hosts
• *.org has about 0.3 million hosts
• Other 2-letter domains (such as *.ch, *.fr, *.uk, *.us, *.mx) cover over 77 countries with roughly 6.5 million hosts

Technology-wise:

• High speed backbone network
• Internet II
• wireless communication (e.g. netmobile)
• security
• home application

Problems:

• Security
• Vulnerability
• Mobility
• Management

Future

• Bright; information revolution (like the Industrial Revolution)
• Will come to home and everywhere; the world will be at your finger tips.
• Will enable us to invent new technologies
• Need to study to stay current and catch the future

• About this document ...