Unit 4 - Networks and the Internet

ARPANET

ARPANET was the first network to connect computers across long distances in 1969. ARPANET stands for Advanced Research Projects Agency Network. It was the first Wide Area Network (WAN).

patents

Patents are registered ideas for techniques, inventions, or processes. By using a patent, a person is protected as the owner of the intellectual property.

queue

A queue is an ordered waiting list of tasks, such as files waiting to be printed.

non-disclosure agreement

Employees and contractors of agencies and businesses are often asked to sign a nondisclosure agreement. This agreement states that they will not share any information that would be damaging to the business with people outside of it.

hardware

Hardware is the physical equipment itself.

hypertext

Hypertext is text in a document that is linked to other information. Early networks used hypertext to link research and other information. Now, hypertext is used in the same way over the World Wide Web.

software piracy

If you create a game that users copy without your permission or without paying you, the users have committed software piracy. Stealing software is illegal.

keywords

Keywords are the words people type into search engines.

packet switching creators

Lawrence G. Roberts and Leonard Kleinrock worked together at the Massachusetts Institute of Technology (MIT) on an early packet-switching idea.

Tim Lee

Lee proposed the idea of hypertext as a way to link information across the web. This was a huge advancement and enabled the evolution of the web search engine and web pages as we know them today.

Minicomputers

Minicomputers allowed computers to be more available for businesses. The first local area networks were born. Made in early 1970s

RARA - Relevance

Relevance: Check the dates on the website. They need to be relatively recent. For instance, any websites that have information that is over five years old are not useful if you are looking for information on computers. Look at the way the page is written; if the author seems to only be telling one side of the story, you may want to look elsewhere.

routing protocols

Routing protocols are rules for how routers communicate with one another and send data.

google search engine founder

Search engine Google founders Sergey Brin and Larry Page made a great contribution by creating a way to get good results from online searches using their expertise in computer science.

social networking

Social networking is online communication through websites and other web services designed to connect people in social ways.

software

Software is the collection of programs that run on hardware.

hop limit

To prevent packets from bouncing around between routers forever, the packet header contains a limit called time to live or hop limit." If a packet exceeds this limit, the router discards the packet.

trademarks

Trademarks represent a brand. Trademarks include logos, slogans, words, phrases, and symbols. These can be registered with the government so that they are officially associated with a business or an organization.

If a citation has a volume, title, and page numbers, it is a:

journal article citation

common network issues

-Equipment not working: make sure all equipment is plugged in, turned on, and connected using correct cables and connections -Computers not connecting: check that switches, routers, and hubs are working, and that configurations are correct -IP address being used by more than one computer: often fixed by having user log off or shut down and log back on -Lost or damaged network files: restore files from backup files - backup files should be updated regularly in case of problems

network software programs

-Firewalls: help keep out unwanted traffic and intruders - many personal computers also run firewalls to keep intruders like viruses out -Antivirus programs: also help keep viruses out of the network -Network operating system (NOS): runs the network and its software components, such as the firewall and antivirus program

hardware components of networks

-Gateway: part of the network that allows communication with other networks -Router: routes data where it should go based on its destination -Hub: makes connections with many devices and then connects them to the network with a single port -Bridge: allows specific kinds of data into different parts of the network -Switch: makes connections between parts of the network or between the network and devices

advantages of wireless networks

-Mobility: People can access the Internet from many locations within the broadcast area. -Cost: It is less expensive because each device no longer needs its own cable. -Security: Users can access the Internet with a network password or a subscription to a broadband Internet service. -Access: With broadband, users can connect to the Internet anywhere their devices can receive a signal, as long as the signal is from the Internet service they subscribe to.

disadvantages of wireless networks

-Skilled labor: Greater skills are needed to set up the network. Users need more technical skill than just plugging a cable into a computer's port. -Authorization: Unauthorized users and unwanted intruders access the network more easily. -Speed: Wi-Fi and broadband are not as fast as wired connections, although adequate for home networks. -Signal Strength: The greater the distance between the router and the computing device, the slower the speed. -Interference: Wireless networks have more interference issues than wired networks do. Devices like wireless gaming controls, microwave ovens, fluorescent lights, and electrical connections that are bad can all cause interference.

techniques for solving network problems

-They try solutions that have worked for the same problem in the past. -They search for solutions to the problem on the Internet. -They ask other network administrators if they have encountered the same problem and how they fixed it. -They check the manuals that come with the equipment for helpful tips.

court thoughts for deciding fair use

1. Is the use nonprofit/educational or commercial? If it is not being used to make money, it is more likely to be considered fair use. 2. How much of the copyrighted work was used? If only a little part of the work was used, it is more likely to be considered fair use. 3. Will the use affect the value of the copyrighted work? If sales of the work are not affected, it is more likely to be considered fair use.

LAN

A Local Area Network (LAN) connects all of the computers in one location, such as in a school or a business. A LAN covers an area of less than one mile. Usually this is a building or a home, but it can also be a cluster of homes or businesses that are on the same network.

backup

A backup is a copy of all data on a network. Backups are made on a regular, usually nightly, basis. This is so that if something happens to the network, all of the data on it will be kept safe and secure, and users will be able to access it once the problem is fixed.

client

A client is the computer that uses the service provided by a server

dead link

A dead link is a link to a web page without any content. Sometimes an error message appears when you click a dead link.

hub

A hub connects many different devices and allows them to connect to the network using a single connection. A hub also forwards any packets it receives to all devices connected to it.

modem

A modem is a device used to connect to the Internet. It translates the signals it receives from the ISP into a form that can be understood by a client computer. It also translates outgoing information sent by the client into the proper signal format required by the ISP. Connected to router

network backbones

A network backbone allows for high-speed connections between major parts of a network. The Internet has a backbone that carries data throughout the world.

network

A network is a set of computers and other peripheral devices, such as printers, that are connected to each other and can communicate with one another. Connections can be made using cables or wireless broadcasts.

passive threat

A passive threat occurs when a person who is not the intended recipient captures data in some way.

router

A router is a device that sends data to the correct destination on a network. It reads the information in a network packet and steers the data to its correct destination. A router makes sure that requests for information are handled efficiently and correctly.

server

A server is the computer that responds to requests from the client computer. The computing devices that help connect computers with other parts of a network. Servers are comprised of both hardware and software.

switch

A switch connects network devices or different parts of a network. However, unlike a hub, a switch sends any packets it receives to only their intended recipients and not to all devices connected to it.

wireless network

A wireless network is a computer network that can be accessed without wires or cables by receiving a short-range radio signal. The signal goes through the modem and is broadcast through a wireless router.

RARA - Accuracy

Accuracy: A site is usually accurate if you can find the same information in other locations, and if the sources cited on the web page actually support the information. Other clues include correct dates, correct spelling, and the same or similar data in other locations.

adware

Adware is advertising that is embedded in software to pay for applications that users get for free. Users who want the software without the advertisements can sometimes pay a fee instead.

active threat

An active threat occurs when an individual disrupts or captures data from a network. This type of disruption can shut the network down completely. Intruders may also try to gain control of individual computers so they can use them to launch attacks on other computer systems.

online predator

An online predator is an adult who tries to make friends with young people to abuse them or in some way exploit the "friendship." An online predator takes advantage of the anonymity of online communications, and may pose as someone of the same age as the young person. This behavior is illegal and endangers the young person.

applications

Applications are programs used by these computing devices to let users do all kinds of things, from using calendars and efficiency tools to playing games and reading e-books.

RARA - Authority

Authority: It should be apparent who is responsible for the web page. A trustworthy site should be able to tell you why they are a good source of information.

bandwidth

Bandwidth measures how much data can flow through a specific connection at one time. It describes the maximum data transfer rate, or capacity, of a network or Internet connection.

broadband

Broadband is a term used to describe any networking technology with a higher bandwidth than older technologies. < 700 kilobits/sec

patches and updates

Bug and security fixes are often made available as a software update, also known as a patch. Patches usually are downloaded from the Internet and installed. Some software, such as antivirus software, updates itself automatically as new patches become available.

PCs

By the 1980s, personal computers (PCs) as well as the Internet in its present form became available.

WiFi

By the 1990s, the IEEE 802.11 standard began the wireless networking revolution. The Wi-Fi Alliance, a trade group formed in 1999, certifies hardware as 802.11 compliant, and holds the trademark on the term "Wi-Fi."

ICANN

Cerf was a leader for a group of people who created standards in naming on the Internet. This group is now known as ICANN (the Internet Corporation for Assigned Names and Numbers). ICANN is a nonprofit organization that has assumed the responsibility for IP address space allocation, protocol parameter assignment, domain name system management, and root server system management functions previously performed under a US government contract.

cloud computing

Cloud computing is the practice of storing data, like pictures, video, music, and even programs on servers that can be accessed through a web browser. This way the information can be accessed from anywhere, and used by many people.

computer virus

Computer viruses are programs that copy themselves onto others' computers. They are often spread by e-mail. Viruses can interfere with normal computer operation. They can slow down the computer or make data unusable by changing it in ways that cannot be reversed. Viruses can also overwrite or even erase the computer's hard drive, so that the user loses all data and applications.

control information

Control information includes all of the addressing information needed to deliver user data and information for the receiver to make sure that the packet was not corrupted during shipment.

copyright

Copyright is the right to copy or reproduce a song, photograph, movie, or written work. Copyright begins as soon as the creator produces the work.

WWW

Created in 1991

creative commons

Creative Commons is a nonprofit organization that helps creators to determine how people can use their work. It does not replace copyright. If an artist wants to share their work, they can choose how it is to be shared using a Creative Commons license. Others can then legally use the artist's work.

DARPA

DARPA (Defense Advanced Research Project Agency) is a US government agency concerned with formulating technologies that the US military can use. The ability to share information and research became crucial during a time of tension between the US and USSR (now Russia).

E-commerce

E-commerce is the ability to do business online. Online banking, online shopping, and online financial transactions of other types are known as e-commerce.

E-government

E-government is the use of the Internet to keep the public informed about what is going on in their towns and states as well as on a federal level. Many cities now allow you to pay the water bills, traffic fines, and other fees online.

encryption

Encryption turns text into a form that is nearly impossible for unauthorized computer systems to read. The resulting text is known as cipher text. A decryption key is needed to decode the cipher text. These encryption methods are especially important in wireless communication networks because wireless communication is easier to intercept than hard-wired communication.

ethics

Ethics is a term that is used to describe how to behave in a way that is for the good of everyone. Ethical people agree to follow these rules, mainly to help people make good choices and not act wrongly toward others.

IP Address

Every computer that is connected to the Internet has an address called an IP address. IP stands for "Internet Protocol." Each device has a unique IP address. This way, the device can be located on the network and receive all of the information that is meant for it. ex: 187.13.245.1

fair use

Fair use is an exception to copyright that allows people to use copyrighted works in limited ways without an author's permission.

fault tolerance

Fault tolerance is the ability of a network to recover after any type of failure. Many networks run "mirror" operations on a separate server to keep the network up and running if there is a failure.

file sharing

File sharing refers to the practice of allowing someone else to have access to files or computer programs. Because there are copyright issues, file sharing is not always legal. The person who holds the copyright must give permission to share the work.

Ethernet

For LANs, Ethernet became the technology standard, replacing competing standards for wired LANs. Ethernet enabled faster and more precise transmission of data. Today, Gigabit Ethernet is the preferred standard, enabling data transmission at rates up to 1 gigabyte per second over fiber optic or wire cables.

hacking

Hacking is the practice of finding weaknesses in a computer or computer network. Hackers, or individuals who practice hacking, are motivated by any of a number of reasons.

The Internet Architecture Board (IAB)

IAB was set up in 1979 by the United States Department of Defense's Defense Advanced Research Projects Agency (DARPA) to address the technical and engineering aspects of the growing Internet. created a set of ethical guidelines for behavior on the Internet.

refining a search

If you do a search and do not get the kinds of results you want, you can change your search keywords to be more specific. This is called refining a search.

IEEE 802.11

In 1997 the Institute of Electrical and Electronics Engineers (IEEE), a nonprofit standards organization, published specification IEEE 802.11 for wireless computer networks. This standard is widely used to implement Wireless Local Area Networks (WLANs).

computer program

In the 1970s the computer program, or set of instructions for the computer to follow, was developed so that non-computer scientists could also use computing in their work.

network packet

Information is sent over networks as binary data files that are formatted into network packets. A network packet contains two kinds of information - user data and control information.

speed of connecting to other people (benefit of networks)

Instead of sending a letter by mail, people can easily and quickly connect to others using networks. Networks speed up many aspects of social interaction.

ISDN

Integrated Services Digital Network (ISDN) is the ability to carry voice, as well as data, video, and other network communications at the same time on telephone lines. These services were developed from voice digitization and allowed users to digitize and send data, video, and other services through telephone circuits.

intellectual property

Intellectual property is the term for copyrighted creations. If you paint portraits or compose song lyrics, they belong to you as your intellectual property. If someone uses them without your permission, that is stealing.

ISPs

Internet Service Providers (ISPs) are companies that offer Internet service. When people connect to the Internet, they connect to an ISP's computers and network.

communication (benefit of networks)

It is easy to share documents, pictures, and other files using a network.

wide-area ring backbone

Nationwide businesses can have their own dedicated backbone that only carries their data in a point-to-point manner. This is known as a wide-area ring backbone.

network administration

Network administration is the management and maintenance of networks within an organization, such as a school or business.

hop

Network packets often must pass through more than one router before they reach their intended host. Each router-to-router leg of the journey is called a hop. On the Internet, it usually takes only a few hops for a packet to reach its destination.

network performance management

Network performance management is an area of network administration that is concerned with how well the network is working. looks at a number of aspects of network performance: the primary connection with the Internet, the way the network is being used (when it is at its busiest, for example), and troubleshooting any problems when there seems to be an issue.

network security

Network security is the group of actions that keep a network safe from potential failures and from attack by intruders. Network security allows companies and other organizations to continue to function.

network topology

Network topology is the way a network is laid out or organized, including all the interconnections.

equipment sharing (benefit of networks)

Networks allow people to share printers and scanners within a group.

screen sharing (benefit of networks)

Networks allow two people in different places to be on the same computer at once. This is beneficial if the people are working on a project together or one of the people needs help.

network hosts

Networks are formed by an assortment of computers and devices, all of which are referred to as network hosts, or network nodes. The term "hosts" is used more frequently to refer to computers, and "nodes" is used more frequently to refer to devices.

how networks are designed

Networks are often designed using what is known as the client-server model. In this design, some network nodes are designated as servers. These computers run special server software and provide services to client computers on demand. Examples of such services include e-mail, database, business intelligence, and cloud computing. The Internet itself is based on this model.

open source

Open source refers to software that exposes its source code for user modification and redistribution. It may or may not be free of cost.

organic links

Organic links are the regular links that appear when you do a search.

peer-to-peer

Peer-to-peer is a type of network topology that does not use a router but shares data directly between computers. Instead of a server responding to requests, computers can communicate directly with one another, allowing files to be directly accessed. Users download a software program that allows this activity.

memory storage (benefit of networks)

People can share storage on a server at their work or school. This storage can be much larger than that on a normal computer. Large files such as movies can be stored and easily accessed on a network.

plagiarism

Plagiarism is the act of taking someone else's writing and passing it off as your own.

RARA - Reliability

Reliability: The website must say where the information came from. You should be able to check to see that those sources are real. Also, think about why the person put up the site.

Robert Kahn

Robert Kahn presented on and talked about ARPANET to interested scientists in 1972. He developed the idea for the way that computers would interact with each other over the Internet, known as the Transmission Control Protocol/Internet Protocol (TCP/IP)

secured networks

Secured networks are network systems that are open only to those with the right credentials. They recognize the user through username and password combinations or by other means.

shared resources

Shared resources refers to information or devices that can be accessed remotely from another computer.

SaaS

Software as a Service (SaaS) is a form of cloud computing. Software applications can be stored and accessed as if they were in the device itself, but they are actually stored online. SaaS enables more people to use the software. This makes computing more efficient and saves on storage.

cookies

Some spyware uses cookies, which are small pieces of information that are stored through a user's web browser. Cookies allow the browser to load pages more quickly and remember settings and other information. These types of uses are not harmful. However, spyware cookies can have harmful effects.

spam

Spam is unwanted communication that comes in many forms. Spam usually takes the form of e-mail messages, but can also be instant messages or text messages on a mobile phone.

speed

Speed refers to throughput, which is the actual amount of data that makes it through a connection per second (mbps). Overhead such as data packaging, as well as competing traffic on the connection, can lower throughput.

sponsored links

Sponsored links are links that companies paid Google to display when people type those keywords.

spoolers

Spoolers are programs that store data temporarily for processing by another program later. Print jobs, for example, are often spooled.

spyware

Spyware sends out information about individuals or their computers without their knowledge.

star topology

Star topology is a type of network topology in which all computers are connected in a "star" formation. The computers are the arms of the star, and a switch, hub, or other computer is at the center of the star.

telecommunications

Telecommunications means the telephones in a company as well as the computer network.

the National Science Foundation

The NSF is a US government agency concerned with research into science and technology. Through the Internet, the NSF saw a way to support science education in schools and research at universities.

hierarchical addressing scheme

The addressing information is presented in a hierarchical addressing scheme. This means that the numbers in the IP address are presented in a particular order based on their locations in the network. This is the same technique used in area and country codes for telephone numbers.

JCR Licklider

The first person to write about connected computers was J. C. R. Licklider, the first leader of the computer research program at Defense Advanced Research Project Agency (DARPA). Licklider talked about his "galactic network" idea to convince others that it would be a good idea. His "galactic network" was his way of describing the Internet before the Internet was created.

transmission types

Transmission types include serial transmission and parallel transmission. Serial transmissions send data one piece at a time, while parallel transmissions send many pieces at a time.

trouble shooting

Troubleshooting is the act of trying to fix what is wrong in a system. It is a creative problem-solving skill that network administrators need to use regularly.

unsecured networks

Unsecured networks are those that can be accessed by anyone. These can be home networks that are not protected by a password. They can also be networks in a public place that do use password protection, such as a coffee shop or library.

user data

User data, also known as the payload, is information sent by a user, such as an e-mail. The payload is bracketed by a header and a trailer, both of which contain control information.

quarantine

Viruses that cannot be removed are put into quarantine, which means that they are made ineffective.

network failure

When a network can no longer carry data smoothly to and from the Internet, the network has encountered network failure. This can result from human error, equipment failure, or a natural event such as a storm. Sometimes a network will slow down and not be as efficient in transferring data.

WANs

Wide Area Networks (WANs) are networks that cover large areas. The Internet is the largest WAN. Networks within countries are also considered WANs. WANs connect many LANs. While LANs are owned by businesses or families, the responsibility for the upkeep and maintenance of WANs is shared by many groups.

wikis

Wikis are websites that make it easy for people to collaborate on creations because everyone has the ability to edit the content in this application. If a group of people wants to create a document, they all work together to contribute their ideas.

wired networks

Wired networks are usually faster than wireless networks because they are connected directly to the hub. Wired networks also do not suffer from interference from other wireless devices or faulty electrical connections.

included in citations

author year of publication title of the article name of the journal the volume and number (or sometimes the season of the year) of the journal page numbers where the article can be found

Disadvantages of networks

networks are expensive and require some skill to set up. Cables, servers, routers, and other equipment need to be kept running smoothly and to be replaced if they wear out. Without them, the network will not work. All of the computers and devices on a network are more vulnerable because they are linked together. If unwanted intruders access the network, they can do harm to many computers, and they can disrupt network connectivity for all network users.

packet switching

packet-switched networks operate like a street grid, where the cars (the packets) can avoid traffic jams by going a different way to their destinations. The network is the roads on which they travel. If the traffic gets heavy, the packets can be rerouted just like cars on a highway. used for ARPANET