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 / MediumInternal/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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