1.  What is the Internet?

• A network of networks that links computers around the world.

  The US portion of the internet includes a number of primary ("backbone") links, as well as a larger number of secondary links, as illustrated below:

  
  

  

  
  

• The internet uses a software protocol called TCP/IP: Transmission Control Protocol/Internet Protocol.

Internet Size and Growth

• 1969: ARPANET with 4 systems.

• The number of connected systems has grown exponentially, doubling annually for the last 25 years:
  

• In about ten more years, if this rate of growth continues, there would be one connected system per human being on Earth! Obviously, the internet will keep growing, but the rate of growth will fall within a few years.

• The user community was originally technical, but is now quite diverse, really being the general public.

How Do People Access the Internet?

Computer Hardware

IBM PC or clone, Mac, UNIX or VMS workstation, or plain terminal.

Network Connection

• Direct Ethernet connections provide 10,000,000 bits/second;

• Dial-up connections provide at most 33,600 bits/second.

Communications software

• Telnet, Versaterm, or Kermit for interactive login;

• TCP/IP, SLIP, or PPP and other tools for general internet use.

Computer Addresses

Numerical

132.235.8.44

Alpha

OAK.CATS.OHIOU.EDU

The alpha form is divided into four parts: specific to general. For example,

• OAK - the individual computer

• CATS - the subdomain or department

• OHIOU - the domain or name of institution

• EDU - the network (United States educational institutions)

Top Level Domain (Network) Names

edu - Education (universities, schools, etc.)

com - Commercial organizations (i.e., business)

mil - Military (army, navy, etc.)

gov - (non-military) Government

org - Other organizations

net - Network resources

Worldwide Network

What can you use the Internet for?

Accessing Services

You can use the internet to logon to a shared computer system, to use its resources, such as library catalogs, or free community bulletin boards (e.g., South Eastern Ohio Regional Freenet), whether that system is in the same room or on another continent. There are two tools that you use:

• TN3270 for IBM mainframes

• Telnet for other systems

Communicating With People

Messages can be sent specifically to you, or they can be "posted" where you might look for them.

• E-Mail

• LISTSERV Discussion Lists

• Usenet News

Accessing Published Information

Although LISTSERV and Usenet news go to many people, it is a selected audience, like CB radio. The next three technologies are methods for public broadcasting, like TV :

• FTP (File Transfer Protocol)

• Gopher

• WWW (World Wide Web)

Accessing Published Information

FTP (File Transfer Protocol)

• File Transfer Protocol: a tool that lets you find and retrieve files stored on other computers.

• Much easier to use with a graphical user interface ("Fetch" on a Mac or "WS_FTP" on a PC with Windows).

• The oldest and easiest way to publish information, so a lot of information is available only through FTP.

Gopher

• Definition: text-menu-based access to a variety of Internet resources.

• Gopher resources can also be accessed through Web browsers, hence many people see Gopher space as just another part of the Web.

• Gopher pre-dates the Web, and is easier for the publisher, so it sometimes has more complete information.

• Very little new information is being published through gopher, because the Web is so much easier to use.

Dick Piccard revised this file (http://ouvaxa.cats.ohiou.edu/~piccard/oacrao/net.html) on November 12, 1996.

Please send comments or suggestions to piccard@ohiou.edu.