The Internet is similar to the highway system in our country. Different governmental

agencies maintain different sections of the highway system. We leave our house and drive on town, county, state, and interstate highways. These roads are paid for by the taxpayers in different governmental jurisdictions but we all are allowed to drive on these roads. If we go to Canada, we drive on highways paid for by the taxpayers in Ontario but they let us use these highways. The Internet is a series of "highways" (phone lines) that are paid for and maintained by different organizations.

Internet

· A system of interconnecting networks using phone lines, satellite, microwave, etc.

· There are national backbones, state-wide regional backbones, local lines connecting to the regional backbone

· The United States backbones are connected to a world wide backbone. This allows a user in Auburn to connect to any Internet site in the world, most countries in the world have a country-wide backbone

· The Internet is a "packet-switching" computer network. When you send a message over the Internet, it is broken into tiny pieces, called "packets," which travel over many different routes between the computer that you are sending from and the computer that you are sending to. Each packet is "switched" by Internet computers along a path that will take it to its destination, but no two packets need follow the same path. The packets are all switched into a destination and reassembled by the destination computer. The "packet-switching" nature of the Internet gives it sufficient speed and flexibility to support real-time communication. Every packet is written in a particular "language," or protocol, called "TCP/IP," which stands for Transmission Control Protocol/Internet Protocol. This protocol is the common language of the Internet.

You sign up with a local Internet Service Provider for a fee per month

Your local ISP has many lines coming into their location so multiple people can be connected to the Internet simultaneously. Your local ISP generates funds by charging monthly fees to many local people.

Your local ISP leases a high speed phone line to Syracuse. Your local ISP contracts (for a fee) with a regional Internet Service Provider who leases a statewide phone line for a regional backbone. The organization that maintains the regional backbone pays for their costs by charging many local Internet Service Providers for connecting to their backbone

The regional ISP leases a high speed line from Buffalo to New York City with connections to local ISP’s in Buffalo, Rochester, Syracuse, Utica, Albany, Poughkeepsie, and New York City

The regional ISP contracts with a company that maintains a national backbone (and pays a monthly fee to this company). The national ISP leases a very high speed line from New York City to San Francisco. The national ISP generates revenue to pay their costs by charging all the regional ISP’s for connecting to the national backbone. There are multiple regional backbones branching of this national backbone giving you the ability to reach any Internet site in the United States.

The national ISP arranges links to other national backbones on this continent and on other continents (in Europe, Asia, etc.) giving us an international world-wide connection.

Each backbone (regional, national) is maintained by a different organization. In the U.S. these organizations are typically non-governmental organizations. In other countries the national government may maintain the backbones. Together all the backbones and ISP’s make up what we call the Internet. Each organization pays for their backbone and charges another ISP to connect to this backbone.

The Internet is the physical wires and equipment in a global packet-switching network of networks. A series of routers that link together networks resulting in a network of networks that travels all around the earth. A router receives transmissions and forwards them towards their destination. Data travels through multiple routers and networks on the way to it’s destination. These linked networks all use a standard protocol. A protocol is a set of rules and procedures for exchanging data between components of a network. The protocol used on the Internet is TCP/IP. This protocol defines the standards of how to build packets of data, indicate the destination address for the packet, and send the packet over the network.

Computers on the CCC network

1. router – a computer that forwards data packets along networks. A router is

connected to at least two networks, in our case a LAN and its ISP’s network.

Routers are the places where two or more networks connect.

2. firewall computer - Firewalls are used to prevent unauthorized Internet users from accessing private networks connected to the Internet. All messages entering or leaving the LAN pass through the firewall, which examines each message and blocks those that do not meet the specified security criteria

3. proxy server computer - A server that sits between a client application, such as a Web browser, and a real server. It intercepts all requests to the real server to see if it can fulfill the requests itself. If not, it forwards the request to the real server. Proxy servers can dramatically improve performance for groups of users. This is because it saves the results of all requests for a certain amount of time. Consider the case where both user X and user Y access the World Wide Web through a proxy server. First user X requests a certain Web page, which we'll call Page 1. Sometime later, user Y requests the same page. Instead of forwarding the request to the Web server where Page 1 resides, which can be a time-consuming operation, the proxy server simply returns the Page 1 that it already fetched for user X. Proxy servers can also be used to filter requests. For example, a company might use a proxy server to prevent its employees from accessing a specific set of Web sites

7. the college’s web server computer – contains college web files, college FTP files, and DNS for CCC client machines sending packets out to the Internet

Internet Access Providers

· ISP

· OSP – online service provider – has member-only features, ex: AOL

· WSP – wireless service provider – provides wireless internet access to users with wireless MODEMS. Example – a notebook with an antenna connected to a wireless MODEM

Sample Speeds on Lines

· Dial-up access - home modem on a standard phone line 56,000 bits per second

· DSL – 10 to 25 times faster than dial-up access over standard phone lines

· Cable TV modem – 25 to 100 times faster than dial up access

· T1 leased line - 1.544 mbps 1,544,000 bits per second

· T3 leased line - 44.736 mbps 44,736,000 bits per second

· OC-3 leased line - 155.52 mbps 155,520,000 bits per second

· OC-12 leased line - 622 mbps 622,000,000 bits per second

· OC-48 leased line - 2.4 gigabit per second line 2,400,000,000 bits per second

Internet governance

The Internet has no central management at all! No single company or organization "owns" the Internet. No central switchboard can shut it down. Each organization on the Internet controls its own computers and networks, and cooperates with its neighbors to create regional networks. The regional networks, in turn, are connected together by national and international high- speed, or backbone communication lines, which in some countries are provided by government institutions. In the United States, the backbones were originally set up by the National Science Foundation. In order to encourage a free telecommunications market, the successful NSF backbone experiment was ended, and backbone service is now provided by telecommunications companies such as Sprint.

· There is no central authority, but there are voluntary governing bodies for things such as registering sites to get Internet site addresses, etc.

· World Wide Web Consortium at MIT in the United States and INRIA in France. The closest thing to setting standards and enforcing rules. They define the language (HTML) and the protocol (HTTP) of the World Wide Web

· World Wide Web Browser program developers have a great influence on what the net browsers do - the two largest are Netscape Navigator and Microsoft Internet Explorer

So what is the Internet?

The Internet is an network of networks based on the protocol called TCP/IP

Internet - a global network of networks, all of which use the same networking protocols so they can communicate and exchange information. The effect is that of one large virtual network

Many institutions have their internet connection on the same computer as their internal functions. In other words, they maintain their Internet web pages on the same disk drive as their internal data (intranet) such as payroll and inventory. It is necessary to establish a security measure (Firewall) to protect the internal data from the internet client browsing the company's web pages. A firewall protects one or more computers with Internet connections from access by external computers connected to the Internet. A firewall, usually created by hardware and software, forms a boundary between networked computers within the firewall from those outside the firewall. A firewall reduces

the risk of intrusion by unauthorized people from the Internet

TCP/IP - Transmission Control Protocol/Internet Protocol

A set of network standards that specify the details of how different brands of computers communicate on the Internet, can be used to communicate across any set of interconnected networks using any operating system and any brand of hardware. TCP is the protocol for the packaging and transmitting internet data and IP is the internet addressing scheme.

Internet 2 - a second global network

With more and more business and residential users on the internet, government and university researchers face internet delays that affect their work. Internet 2 improves computer connections among campuses and has ways to prioritize information so video presentations cruise past less urgent e-mail on the internet. Initially started in 1997 by two dozen universities contributing $2.5 million each, Internet 2 is a totally separate network used only by universities and government research facilities. The National Science Foundation is underwriting much of the main wiring. The main backbone of Internet2 (put in use Feb. 1999) is a 13,000 mile 2.4 gigabit per second line connected to 150 universities.

*Internet Packets may contain data for the following uses*
Electronic mail	text messages (and attached files and graphics) sent through the Internet to a specified individual. Uses SMTP protocol
IRC (Internet Relay Chat)	users on client machines log in to a server computer with Internet Relay Chat software. The IRC server sends a client’s typed message to all other clients logged in to the server with the result being a real-time text chat. As the user types text, it displays on the screen of the other people logged in to the server
MUD (multiple user dungeon or Multiple user dimension)	text or graphics-enhanced virtual online environment used for everything from cooperative research to role playing in a game. Multiple users sign on to a single server and play an interactive game
video conferencing - example: Cu-see-me	users connected to a server, each user has a camera and microphone and can view and listen to the other participants
Internet phone	a service that provides telephone connections through the Internet. Users can place calls from their computer to other Internet computer users or to a server in a remote city that places a call (a local call for that server) over regular phone lines
remote login - Telnet	terminal emulation where a user is connected to a remote host using the Internet as if the user were directly connected to the host. Allows the user to “take control” of the remote host and perform work (run programs) on the host as if the user were sitting at a terminal at the site where the remote host is located
file transfer protocol- FTP	a standard way to transfer (upload and download) files between computers. The method has built in error checking.
listserver or mailing list	discussion groups on the Internet that link a group of people with common interests. Users subscribe to a mailing list and then receive as e-mail every message posted to the list. The mailing list server does a one to many distribution of mail it receives
electronic bulletin board or NewsGroup	Users “post” messages by sending e-mail to a news group server. Other people browse the postings and read the e-mail postings. Newsgroups have a hierarchical list of categories. Some newsgroups are moderated or controlled to filter out irrelevant and redundant messages
World Wide Web	a graphical interface for the Internet that is composed of Web servers that provide access to stored documents (disk files) which include hyperlinks and multimedia. Uses HTTP protocol. These files have codes written in the programming language HTML (hypertext markup language). A user’s browser program accesses these files, interprets the HTML code and displays the file on the user’s computer screen.
Instant Messaging	IM is real-time Internet communication service that notifies you when your “buddies” are online and then allows you to exchange messages with them, like a private chat room
VoIP – Voice over Internet protocol	enables people to use the Internet as the transmission medium for telephone calls, phone companies and cable television companies offer this service for both local and long distance phone service. An example would be a service that allows voice mail to be translated into e-mail

E-mail - A service that permits a user to electronically send memos to another person or group of people. The user can attach disk files to the e-mail. E-mail programs allow you to receive mail, send mail, keep a file of mail received and sent, delete mail you don’t want to keep.

A method to electronically transfer, or mail, messages from an electronic mail account on one computer to an electronic mail account on another computer.

How to e-mail - Using an e-mail program, you address an electronic message to someone who has an e-mail account on another computer. You type your message and sent it to the recipient’s account on the recipient’s host computer

How does it get there

· You use the electronic mail program to prepare the message

· It is “packaged” by your host computer using the Internet protocol and sent over lines to the regional backbone

· The packet is switched to the next backbone, etc. Until the packet arrives at the address indicated

· The mail is stored in the e-mail system on the host where the recipient can read it, reply, delete it, etc.

Internet mail addresses - JONES@Cayuga-CC.edu

· JONES= your unique description such as your last name

· @Cayuga-cc = site, where are you (Cayuga Community College)

· .edu = domain, type of site Cayuga is an educational site

Typical Domains - although there is no guarantee that an organization has the correct domain for their business. Ex. The address syr.org was recently offered for sale to the highest bidder so anyone could have the .org extension

· .Edu = education ftjones@.cayuga-cc.edu

· .Gov = government alincoln@whitehouse.gov

· .Mil = military tjjones@ft-swill.mil

· .Com = commercial org. Bruno@pepsi.com

· .Org = non-profit organization, etc, Fred@redcross.org

· .Net = network. Computers that help to run the Internet.

Newer domains

· biz = businesses

· .info = organizations providing general information

· .name = for personal web pages

· .pro = for professionals like doctors and lawyers

· .museum = museums

· .aero = aerospace industry

· .coop = co-operatives such as credit unions

sample e-mail screen

IRC - Internet relay chat (chat rooms) - see the site http://www.talkcity.com

IRC closely resembles the chat systems that have sprung up on commercial on-line services. The users on IRC can be logged-in to hundreds of different computers around the world, and they may speak any number of languages, such as French, Spanish, Chinese or Hebrew. While most IRC sites use only text, many new IRC sites exist in graphical environments.

· A recreational communication system, interactive communication with a number of people all linked to a common computer, the IRC server

· Allows you to communicate with people all over the world by typing your message and reading the messages other people are posting

· Chat room where IRC client users link to an IRC server and have an online chat will all people linked to that chat room

The sample screen below demonstrates entering the chat server. You must type in your screen name so people can refer to you during the chat and then you select a chat room topic. There are many chat rooms open for you to visit.

Here you see some typical chat room displays. Some chat rooms have a bigger screen for more of the actual conversation than this room. You can click on a name to talk to one person or type text that will be displayed on everyone’s screen.

this is an America On Line chat room
1 = the chat screen that displays everyone’s chat comments
2 = the people in the chat room
3 = the place where you can send your comments to the chat room

Below you see another chat room display. Some chat rooms have a bigger screen for more of the actual conversation than this room. You can click on a name to talk to one person or type text that will be displayed on everyone's screen

IM – Instant Messaging – (like a private chat room) build a “buddy list” on an IM server, log on the IM server and it will check to see if your “buddies” are logged on. You can send messages to any buddy who is logged on

MUD - multi-user dimension

Imagine a world in which you could change every aspect of yourself - your body, your name, your actions - and then imagine that you could also change the environment in which you lived. You could make yourself into a astronaut, and work with other astronauts from around the world in the building of a space station. Or you could add on to a mysterious hotel inhabited by aliens, ghosts, and major American authors. All of this is possible on the Internet, and it's called MUD, the Multi-User Dimension (or Multi-User Dungeon). It is much like the computerized text adventure games in which you would type "go north," "kill troll," and so on, but a MUD differs from these games in three fundamental ways: you can create your own character, the other characters that you meet are actually real people, and you can participate in the building of the game environment.

A MUD (Multiple User Dimension, Multiple User Dungeon, or Multiple User Dialogue) is a computer program which users can log into and explore. Each user takes control of a computerized persona/ character. You can walk around, chat with other characters, explore dangerous monster-infested areas, solve puzzles, and even create your very own rooms, descriptions and items.

· Multi-player games that let a lot of users all connect to the same machine to play at the same time. See the site http://www.geocities.com/Area51/Labyrinth/4535/