Wednesday's 4RQs #2 from ch.10

1.)Key terms:

• Access control Software: a software that only allows users to access according to the user's needs


• active badge: a microprocessor-controlled ID badges that broadcasts infrared identification codes to a network receiver


• antivirus:a program designed to search for virus, alert the users, and destroy the virus


• authentication mechanism: a security measure that make sures only legitimate users have access to the system by asking potential users to identify themselves


• authorization mechanism: a security measure that guarantees that users have permission to perform a particular task


• autonomous system: a complex system that can assume almost complete responsibility for a task without human input


• back up:the process of saving data- especially for data recovery


• biometric: measurements of individual body characteristics


• computer crime: an crime accomplished though knowledge or use of computer technology


• computer security:protecting a computer system and information from...


• DoS attack:(denial of service) a type of computer vandalism that bombard servers and Web sites , denying service to legitimate clients and customers


• encryption: a secret numerical code that can be used to scramble network transmission


• firewall: a tool used to keep internal networks secure while enabling communication with the rest of the Internet


• hacking: electronic trespassing and vandalism


• identity theft: the crime of obtaining enough information about a person to assume his or her identity


• logic bomb: a program designed to attack in response to a particular logical event or sequence of events


• malware: malicious software (worms, viruses, etc.)


• passwords: the most common security tool used to restrict access to a computer system


• sabotage: a malicious attack on work, tools, or business

3.)Describe the typical computer criminal. How does he or she differ from the media stereotype. the typical computer criminal is a trusted employee with no criminal record who is tempted by an opportunity.Greed, financial worries ,or personal problems motivate this person to give in to temptations. This is different from the stereotypical criminal who is described as a young, bright, technically savvy,white, middle class, male who in addition to programming his computer, may break into others. The stereotype classify the criminals young, white and middle class, but that is just a generalization.

9.)Every afternoon at closing time the First Taxpayer's Bank copies all the day's accumulated transaction information from disk to tape. Why? They do this to backup their work and take precautions, data and software are backed up on to disks or tapes at the end of the day to allow them, if necessary, to go back several days weeks, or years to reconstruct files. It is also done to secure the files in case something happens.

10. In what ways can computer security protect privacy of individuals? In what ways can computer security threaten the privacy of individuals? Protect privacy: Computer security protects us from destructive viruses, illegal interlopers,crooked coworkers, software pirates, and cybervandals who can erode trust, threaten jobs and make life difficult for everyone. It also prevents our personal information from getting into the wrong hands. Threatens privacy: The complex procedures, virus protection programs, intellectual property laws and other security matter, which are used to protect our privacy , if carried to far can interfere with our work and individual human rights. Government and corporate databases gather information about us without our knowledge. In order to protect us, they invade our privacy.

Ch.10 4RQs Monday

2. Why is it hard to estimate the extent of computer crimes? It is hard to estimate the extent because some crimes go undetected and are sometimes not reported (such as to prevent negative publicity) 4. What is the most common computer crime? Who commits it? What is being done to stop it? Theft by computer is the most common computer crime.It is when computers are used to steal money, goods, information etc.. A variety of people are usually involved with it such as , employees, programmers,clerks,and managers. To prevent this from happening, companies are creating more secure Web sites, the FBI gets involved (with large cases), people are encouraged to use firewall,encryption software and passwords. 6. Describe several types of programs that can be used for software sabotage. viruses: Software that spreads form program to program or from disk to disk, and used infected program or disks to make copies of itself worms: similar to viruses but they travel independently over networks looking for uninfected workstations to occupy. Trojan horses: A program that performs a useful task while at the same time carrying out some secret destructive act. spyware: technology that collects information from computer users without their knowledge or consent 7. What are two inherent characteristics of computers that make security so difficult? 1) Computers do exactly what they are programmed to do. And they can be reprogrammed 2)It can only do what it is programmed to do, meaning that it cannot protect itself from malfunctions and attacks.

Ch.9 4 RQs #2

5.Explain the relationship between the client server models and the fact that different users might experience different interfaces while accessing the same information.

The client and server were relationship is a hierarchical one. one computer is the server and other are the clients. Since the server is going to serve all the requests of its clients, its interface is more complex. The clients interface is more simple, to shield the user from the complexities. The client get what it needs in an understandable way.

6. What do email addresses and URLs have in common?
They both use the same domain-naming scheme. the both include information about the host and domain.They both are used to pinpoint or specify a a specific "address".

9.Why is file compression important on the Internet?
Data compression is the process of encoding information with lesser bits than it would usually use. It is important because it allows files to be transmitted easily and faster over slow intenet connection.

11. How does push technology differ from standard Web page delivery techniques? How is it used?
Push technology is different from the standard Web page delivery because it allows to subscribe to a service or specify the kind of information you want to receive and the server delivers that information periodically and unobtrusively to you.. It works by allowing the client to use a browser to pull information from server machines. The browser initiates a request and then the information is delivered to the client.

10 Top Level Domains

.com: Commercial site
.net: network administering site
.edu: education
.mil: military
.org: organization (non-profit
.museum: Museum site
.info: information
.gov: government
.coop: Cooperative business
.pro: Licensed Professional
.biz: Business

Ch.9 4 RQs

1. Key terms:
Internet2:An alternative Internet-style network that provides faster communications for universities and research institutions

TCP/IP: Transmission Control Protocol/Internet Protocol)"language" for the internet that allows cross-network communication for almost every type of computer or network.

Packet-switching: A standard technique used to send information over the internet.A message is broken into packets that travel independently from network to network towards their common destination, where they are united.

internetworking: connecting different types of networks and computer systems

open standards: not owned by any company

IP address: a string of 4 numbers separated by periods or dots that serves as an address for computers on the internet.

Static IP address: an address that is permanent

Dynamic IP address: address used for computers that are temporarily connected to the net, such as with dial up connection.

Next Generation Internet: refers to Internet Protocol Version 6. It solves the problem of address shortages and other improvements

multicasting: is a more efficient way for the same information to be transmitted to multiple Internet connected devices

DNS - Domain name system: A system that translates a computers numerical address into an easier to remember string of names separated by dots

domains:class of internet addresses indicated by suffixes such as .com, .org. gov.

(more will be added )

2.Why is it hard to determine how big the Internet is?
-It is growing to fast
-Its is decentralized, there is not a central system to track user activity
-It doesn't have hard boundaries. It is hard to say what belongs to the internet.

3. Why are TCP/IP protocols so important to the functioning of the internet? What does it do?
It functions as a "Language" the allows cross network communication for almost any type of computer or network. Without it you would not be able to have cross network communication between different computers and networks.

4. How does the type of Internet connection influence the things you can do on the Internet?
If you have high speed internet you can access a lot of things really quickly, without much waiting. But if you have bad internet connections, some websites might no open or might take a really long time open making then not worth the wait. This also makes it hard to view videos and other multimedia.With bad connection you try to do only what is really necessary.

Chapter 8 Review Questions (total of 8 questions)

2.Give three general reasons for the importance of computer networking?

• Networks enable people to share computer hardware resources,reducing costs and making it possible for people to benefit from powerful computer equipment.
• Networks allow people to share data ans programs, increasing efficiency and productivity
• Networks allow people to work together , in way that would otherwise be difficult.

5. Under what circumstances is a modem necessary for connecting computers in networks? What does a modem do?

A modem is a hardware device that connects a computer to a telephone line.Modems are necessary when you want to use a telephone network to connect remote computers. It job is to convert digital signals into analog signals and vice versa.

6.Describe at least two communication softwares.

One communication software is known as NOS or a network operating system.. It is for users who work exclusively on a local area network.It must respond to requests from many computers and must coordinate communication through out the network.
Another communication software is the terminal emulation software. It is the most basic communication software outside of LAN.It enables a computer to function as a simple input and output device for sending messages to or receiving messages from the host computer.

7. How can a file server be used in a student computer lab? What software issue
would be raised by using a file server in a student lab?

In a student lab a file server can be used to store file created by students and softwares and sharing them with ease.A software licensing issue that can be raised since some but not all licenses allow the software to be installed on a file server as long as the number of simultaneous users never exceeds the number of licenses copies.

8. What are the difference between email and instant messaging systems?

One of the main differences is that instant messaging is Real -Time communication and is based on typed text while e-mails are not and can include text, images and more.

9. Describe something you can do with email that you can not do with regular mail.

Using email you can send messages within minutes and get a quick response. You don't have to go and drop the letter at a post office.

10. Describe several potential problems associated with email and teleconferencing.

-If the recipient views an HTML-encoded message with a mail program that does not recognize HTML, the formatting doesn't appear.
-Some messages can carry web bugs and viruses
-Junk mailers can get information about you when you read their messages
-they are vulnerable to machine failure, network glitches, and security breaches
-messages can be misunderstood

13. Why is netiquette important? Give some examples of netiquette.

Netiquette is important in ensuring that others have a pleasant Internet experiences. Some examples of good network or Internet etiquettes are respecting the privacy of others, not abusing your power, and avoiding 'flamewars'.

chapter 8

social networking in plain english video

Networking and digital communication
-Artur C. clarkes prophesy: it a scientist says that some thing is possible he is right but if he says that it is not then he is wrong
-he predicted the use of geostationary communication satellites

comp network: system of 2 or more comp. linked together. helps in communication etc

LAN : comp close to each other, local,
-each comp is a node on a network

wireless network: each node has a tiny radio to connect it to the network/

MAN: link s many lans

WAN: extended over large distances
routers: hardware tat route messages as they travel between networks

GPS: global positioning system
024 satellites that go around the earth and give us info
-a network not connected to the internet

ATM: Automated teller machine: special terminal linked to banks computer
network interface card:
-adds additional serial port
-direct network connection
-controls data transfer from ram to network cable

Modem: connects computer port to phone line
transition speed is in bps )bits per second)
computer send s digital signal
modem converts the signal from digital to analog and vice versa

Broadband connection: connection with much greater bandwidth
-DSL, cable modems,high-speed wireless, satellite dishes

fiberoptic connection: better than DSL and cable modems. substitute copper wires. uses speed of light.

wire less: lightning fast connection is useless if you are away from your desk most of the time
fastest growing wireless tech is wi-fi (for lan)

blue tooth allows many device up to 30 ft can communicate with each other
-possible to create a personal area network

possibilities:
-pacemaker and calling 911
- pen scans business cards and sends info to PDA in brief case
-wrist band that gives info of accident victims to the doctor
-phone tells you sales in store for clothes your size as you walk by it

Communication softwares: establishes protocols by hardware

NOS: systems handles communication between workstations
peer to peer
Networks: share hardware ex. printer
Softwares: file servers
people : groupware

Email: send and receive messages through networking uses ASCII code
some don't always show HTML. but risk of web bugs. Mailing list help you subscribe to sites and get info in your inbox
newsgroup; get daily info. there are moderators

asyncronous communication: sender and receiver dont have to be on at the same time

IM : real-time , need to be on a t same time

computer telephony integration: link comps and phones for better

VoIP: use Internet to make voice calls. easy, less expensive
disadvantage: no 911 services, dont work in black out
-no quality guarantee


Social networking: twitter, facebook

Emails problems: spam, junk mail, security, threat to privacy, vulnerable to machine failures
cookies: can be used by snoopers to get info about you
wireless: issues of access, security, privacy

many services will be taken over by digital delivery systems
telecommunication is changing

summary:
LAN: comps are close together, have radio transmitters
WAN are more distant
Computers are connected together by the internet
most comp use Ethernet

wireless revolution is far from over.