comp sci study guide 5

List the necessary components of a wireless network.A picture will do just fine.

The necessary components of a wireless network are: 1. Network interface card (NIC) 2. Access Point (AP) 3. Router

List at least three pieces of information in the metadata of a file.

User ID File Size File Permission

VOIP

Voice over Internet Protocol is a category of hardware and software that enables people to use the Internet as the transmission medium for telephone calls by sending voice data in packets using IP rather than by traditional circuit transmissions of the PSTN. *Voice over Internet protocol - a phone connection through a personal computer with any type of broadband Internet connection.

Ethernet

a system for connecting a number of computer systems to form a local area network, with protocols to control the passing of information and to avoid simultaneous transmission by two or more systems.

What happens to the data in deleted files (files you delete by clicking on the delete key)?(BTB)

"When a user 'deletes' a file, it's not really gone. Deleted files are sent to the Trash folder. At this point, files can still be recovered." However, even if the Trash folder is emptied, it doesn't mean the file has disappeared completely. "But the longer a deleted file is left on a drive, the greater the chance the file cannot be recovered,"

Internet

A global network connecting millions of computers, making it possible to exchange information.

web crawlers (or spiders)

A program that automatically fetches Web pages. Spiders are used to feed pages to search engines. It's called a spider because it crawls over the Web. Another term for these programs is webcrawler.

search engine

A software program you can use to find Web sites, Web pages, and Internet files.

hotspot

A specific geographic location in which an access point provides public wireless broadband network services to mobile visitors through a WLAN. Hotspots are often located in heavily populated places such as airports, train stations, libraries, marinas, conventions centers and hotels. Hotspots typically have a short range of access.

Protocol

An agreed-upon format for transmitting data between two devices. The protocol determines the following: -the type of error checking to be used -data compression method, if any -how the sending device will indicate that it has finished sending a message -how the receiving device will indicate that it has received a message

What is the difference between bandwidth and latency?

Bandwidth- How much data can i transfer per secondLatency- Amount of time it takes a packet of data to move across a network connection.

Compare and contrast peer-to-peer networks with client-server networks.

Client server networks have a central server that provides information, data and resources to other nodes (clients). With peer to peer networks, each computer can directly supply resources, information etc to all other computers on the network. They both allow information to be shared however client server networks share information through central servers while peer to peer networks allow each computer to share information independently

Define the term network and list three advantages provided by networks.

Collection of hardware components & computers interconnected by communication channels allow sharing of resources & info. 1. setup a single server computer to handle all information requests/login requests for network, only need 1 username & password for each user 2. Info control is easier 3. Maintenance costs drops

What is steganography? How does it differ from cryptography? (BTB)

Cryptography or cryptology is the practice and study of techniques for secure communication in the presence of third parties called adversaries. More generally, cryptography is about constructing and analyzing protocols that prevent third parties or the public from reading private messages Steganography is the practice of concealing a file, message, image, or video within another file, message, image, or video. Steganography requires two files: one is the message which has to be hidden, the other is the cover file which is used to hide the date/message.

DNS

Domain Name System (or Service or Server), an Internet service that translates domain names into IP addresses. Because domain names are alphabetic, they're easier to remember. The Internet however, is really based on IP addresses. URLs to IP addresses

HTTP vs HTML

HTTP- the language used by web clients (you) and the web server (internet explorer) HTML- standard language used to create web pages

HTTP

HyperText Transfer Protocol, HTTP is the underlying protocol used by the World Wide Web and this protocol defines how messages are formatted and transmitted, and what actions Web servers and browsers should take in response to various commands.

HTML

Hypertext Markup Language, a standardized system for tagging text files to achieve font, color, graphic, and hyperlink effects on World Wide Web pages. HTML defines the structure and layout of a Web document by using a variety of tags and attributes.

What is the difference among LAN, MAN, WAN?

In LAN communication devices interconnected within a geographically limited area, such as a building or a campus. In WAN network spread across countries without any limits of distance for this satellites are used. MAN covers a larger area than that of a LAN and smaller area as compared to WAN. It connects two or more computers that are apart but resides in the same or different cities. It covers a large geographical area and may serve as an ISP

IEEE

Institute of Electrical and Electronic Engineers. International organization with a focus on electrical, electronics, and information technology topics. IEEE standards are well respected and followed by vendors around the world.

IETF

Internet Engineering Task Force, the main standards organization for the Internet. The IETF is a large open international community of network designers, operators, vendors, and researchers concerned with the evolution of the Internet architecture and the smooth operation of the Internet.

IMAP

Internet Message Access Protocol, a protocol for retrieving e-mail messages. The latest version, IMAP4, is similar to POP3 but supports some additional features. For example, with IMAP4, you can search through your e-mail messages for keywords while the messages are still on mail server.

ISP

Internet Service Provider, it refers to a company that provides Internet services, including personal and business access to the Internet. For a monthly fee, the service provider usually provides a software package, username, password and access phone number. **(Internet Service Provider) A company that provides access to the Internet.

SSL/TSL

Secure Sockets layer / Transport Layer Security - An encryption layer of HTTP that uses public key cryptography to establish a secure connection.

A school with 20 stand-alone PCs is considering networking them together and adding a file server. Give three possible benefits of doing this.

Sharing of resources such as printers and scanner scan be possible. Can share data and access file from any 20 machines

SMTP

Simple Mail Transfer Protocol, a protocol for sending e-mail messages between servers. Most e-mail systems that send mail over the Internet use SMTP to send messages from one server to another

packets

Small chunks of information that have been carefully formed from larger chunks of information. A piece of a message transmitted over a packet-switching network. See under packet switching. One of the key features of a packet is that it contains the destination address in addition to the data. In IP networks, packets are often called datagrams.

IPv6 vs IPv4

The Internet Protocol version 6 provides a large number of new addresses to route Internet traffic, using "from" and "to" addresses written as colon-hexadecimal notation, such as "fe80::42:acff:feaa:1bf0". The Internet Protocol version 4 is the dominant protocol for routing traffic on the Internet, specifying "to" and "from" addresses using a dotted decimal such as "122.45.255.0". **IPv4 is 32-Bit IP address whereas IPv6 is a 128-Bit IP address. IPv4 is a numeric addressing method whereas IPv6 is an alphanumeric addressing method. IPv4 binary bits are separated by a dot(.) ... IPv4 offers 12 header fields whereas IPv6 offers 8 header fields.

TCP/IP

Transmission Control Protocol/Internet Protocol. Protocol that connects computers to the Internet. Tells computers how to exchange information over the Internet.

URL

Uniform Resource Locator; a location or address identifying where documents can be found on the Internet; a Web address

Describe the process followed by packet switching in transferring data.

When traversing network adapters, switches, routers and other network nodes, packets are buffered and queued, resulting in variable delay and throughput depending on the traffic load in the network

WWW

World Wide Web; a system of interlinked hypertext documents contained on the Internet. The documents are formatted in a markup language called HTML (HyperText Markup Language) that supports links to other documents, as well as graphics, audio, and video files.

Open standards

are standards made available to the general public and are developed (or approved) and maintained via a collaborative and consensus driven process. "Open Standards" facilitate interoperability and data exchange among different products or services and are intended for widespread adoption.

browser

is a software application used to locate, retrieve and display content on the World Wide Web, including webpages, images, video and other files. As a client/server model, the browser is the client run on a computer or mobile device that contacts the Web server and requests information.

What is metadata (BTB)

summarizes basic information about data, which can make finding and working with particular instances of data easier.