CSCI 101Notes

The Internet and Networks

The Internet grew out of an experiment funded in the late 1960’s by the ______where ______computers were connected. Called ARPANet. First computer communication in 1969.

Today the Internet connects ___millionsof (a billion)__ computers.

The Internet is a network of networks Internet ≠ WWW ≠ Cloud

Protocol______

Some of the services and resources available through the Internet include:

Applications/Resources / Services {protocol}
Online stores, auctions / WWW {http}
Online news and magazines / E-mail {mailto}
Libraries / Video conferencing {callto}
Portals / Down-/up-load (file transfer) {ftp}
Travel reservations / Remote login {telnet}

The major components of the Internet are: (Internet service providers, servers, browsers)

  • ______companies that make the connections (pg 269)
  • ______computers that provide services information
  • ______software used to access the Internet

Four factors that allowed the Internet to grow explosively: (Review - in History notes)

______

The unique address for each page or resource in the Internet is called a URL, which stands for:

______

The parts of a URL include

or

Some common top-level domains include ______

The World Wide Web is an Internet-based hypertext system

Web pages are constructed using HTML, which stands for______

Some of the most popular browsers include ______

Caution: Some web pages display differently in different browsers.

A Plug-in is software that gives the browser added capability.

This is similar to ______for hardware.

Example Plug-ins:______

Some of the problems or shortcomings of the Internet include:

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CSCI 101Notes

The Internet and Networks

  • Unregulated
  • Useless web sites
  • Misinformation and misstatements
  • Concern - government censorship
  • Plagiarism
  • Unwanted and unintentional access
  • Netiquette

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CSCI 101Notes

The Internet and Networks

What is “netiquette”?______

Identify at least two netiquette recommendations from the URL’s below.

Netiquette Core Rules:

Rules with a summary:

A network is - the collection of elements needed to enable information exchange between people, systems, or people and systems: hardware, software, transmission media, services

Types of signals sent across a network (Review – check your notes ):

1. ______– a continuous range of values. Ex______

2. ______– limitednumber of discreet values. Ex______

•Digitize– means converting analog signals to digital (1s and 0s)

Types and examples of media:

1. Guided -

•copper, twisted-pair lines

•coaxial cable

•fiber

2. Unguided -

•propagation through air, sea, water, vacuum

•radio waves (RF)

•infrared, microwave, light

Network Hardware: Modem, NIC Switch, Router,

Modem

What it does: Converts digital signals to analog signals

•Must be one at each end

•(dial-up) : up to 56 Kbps

Example modems: ______

______

NIC

Stands for: ______

What it does: Allows exchange of data via a LAN. Required in every PC or server connected to a LAN. Sometimes called the Ethernet card.

Switch or Router?

______: Used to transmit data on a single network. Connects local devices together.

______: Transmits data between networks. Connect distant or incompatible networks. Forwards traffic to proper destinations

Today, nearly all switches use Ethernet; devices are connected by coaxial cable, or more commonly by twisted-pair copper cable or even by fiber

Network Data Flow

Protocol - rules for exchanging data and communication

Data flows according to a protocol

Example: TCP/IP (Transmission Control Protocol /Internet Protocol) for the Internet

Bandwidth - ______

Narrowband - ______

Broadband - ______

Network Types (distinguished by __geographic location_)

•______- Connects cell phones, PDA, etc. to a network

•______- Limited geography: a campus or a building

•______- Covers a medium area, such as a city

•______- Covers long distances, May interconnect multiple LANs,

The Internet is an example ______

Ethernet

Is a ___LAN_ technology

Is a _protocol__ for computer communication. 10 or 100 Mbps, 1 Gbps, 10 Gbps

Advantages: Efficient at moving data

Disadvantages: Complex, requires switch/router

Two network configurations: client/server and peer-to-peer

A ______is a computer that provides services; controls the sharing of network resources

A ______is a computer that requests services. Access shared network resources.

Most popular network servers: communication, file, ______, ______,

Examples of network applications:

  • Home

A home network is usually a peer-to-peer (p2p) network. Each node on the network can communicate with every other node on the network. Computers have similar capabilities.

Some reasons to build a home network are to play multi-computer games and share: ______

______, ______

The elements of a home network include: PCs, NICs, Cabling, switch/router

Net Neutrality - Every packet is equal to every other packet, regardless of type, destination, or owner.

Connecting to the Internet

Speed / Price / Medium
Internal/Ext Modems / 56Kbs
33Kbs / POTS
Telephone line
DSL / Average 3.7 Mbps / POTS
Telephone line
Cable Modem / Average: 10Mbps  / Coaxial Cable
T-1
T-3
OCx / 1.5 Mbps
12-44.736 Mbps
155Mbps and up / $200
$1,800 - 3,500
$3,500+ / Fiber Optic
3G
4G / Claim 7-21MB (Actual 5avg and 20max) / Varies / Wireless
Cellular modems / 9.6K to 56K / Varies / Wireless

Download vs Upload (in terms of server and client)

Download ______to______

Upload ______to______

For further insight on networks.

Video on how networks work:

Networks explained:

Check your internet speed:

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