(Local Area Network) An interconnected group of computers and peripherals located within a relatively limited area, such as a building or campus.
(Wide Area Network) An interxconnected group of computers and peripherals that covers a large geographical area, such as multiple branches of a corporation.
(Metropolitan Area Network) A public, high-speed network that can transmit voice and data within a range of 50 miles
Any device, such as a gateway, hub, or router, that is used to broadcast network data, boost signals, or route data to its destination.
A network in which all devices are connected in a circle with each device having exactly two neighbors
A network configured with a central connection point or hub for all workstations and peripherals.
A net work arranged in such a way that each device is connected to many other devices. Data traveling on a mesh network can take any of several possible paths.
Broadband vs. Narrowband:
Broadband: A term used to refer to communications channels that have high bandwidth
Narrowband: A term that refers to communications channels that have low bandwidth
Packet Switching vs. Circuit Switching:
Packet Switching: A technology used by data communications networks, such as the Internet, where a message is divided into smaller units called "packets" for transmission
Circuit Switching: The method used by the telephone network to temporarily connect one telephone with another for the duration of a call.
A network that uses a building's existing powerline cables to connect nodes; also called HomePlug, HPLC, or HomePLC.
Advantages/Disadvantages of Wireless
Power spikes are much less likely to run through cables to damage workstations
Was expensive. Now prices equalized.
Network vs. Wired Network:
Wireless slower than wired: Wireless signals are susceptible to interference from devices. Interference affects wireless signal, data must be re-transmitted. That takes extra time.
Limits the range of wireless network: Type of signal, the transmitter strength, and the physical environment. Data signals fade as the distance between the network devices increases. Signal range can also be limited by thick walls, floors or ceilings.
Wireless Encryption -
Scrambles the data transmitted between wireless devices and then unscrambles the data only on devices that have a valid encryption key.
Wireless Encryption - Types/Methods: WEP: (Wired Equivalent Privacy)
Original wireless encryption.
Designed to provide a level of confidentiality similar to that of a wired network.
Original version: very easy to bypass.
2nd version: uses stronger encryption but has several flaws that can easily be exploited by hackers.
Plaintext vs. Ciphertext:
Plaintext: An original message-one that has not yet been encrypted- cleartext/plaintest.
Cipertext: An encrypted message.
Created in 1969, connected computers at UCLA, Stanford Research Institue, University of Utah, and University of California at Santa Barbara.
An original diagram of the ARPANET included four nodes, depicted as circles.
ISP: (Internet service provider)
A company that provides Internet access to businesses, organizations, and individuals.
The internet backbone includes high-speed routers and high speed fiber-optic links. Parts of the backbone maintained by different communications com panies are connected at network access points (NAPs)
Operates: routers, communication equipment, and other network devices that handle the physical aspects of transmitting and receiving data between their subscribers and the Internet.
(Transmission Control Protocol/Internet Protocol) The primary protocol suite for transmitting messages over the Internet.
Static vs. Dynamic IP Addresses:
Static: A permanently assigned and unique IP address, used by hosts or servers.
Dynamic: A temporarily assigned IP address usually provided by an ISP.
Private vs. Routable IP Addresses
Private: An IP address that cannot be routed over the Internet.
Routable: A network address that can be routed over the Internet; contrast to private IP address
A device that modulates and demodulates a signal, typically used to send data from a computer to the Internet over telephone, cable television, or satellite networks.
(ISP P:provider) A company that provides vdf5Internet access to businesses, organizations, and individuals.
a fixed Internet connection that uses a voiceband modem and telephone lines to transport data between your computer and your ISP.
A communications device that can be used to connect a computer to the Internet via the cable TV infrastructure.
A device that sends and receives digital data to and from computers over telephone lines.
a device that connects a computer to a satellite for purposes of accessing the Internet.
: Fixed wireless Internet service based on Ethernet protocols with a range of 30 miles and a transmission speed of 70 Mbps.
(File Transfer Protcol) A set of rules for uploading and downloading files between a client computer and a remote server
P2P: file sharing
A practice in which individuals can obtain music, video, and other types of files from other users on a network; sometimes the files are shared without authorization from the copyright holder
An exploit used by hackers to locate computer ports that can be use for surreptitious access.
One for the most effective steps you can take to secure your computer from intrusions is to install a router.
Intended to work on LANs to monitor and direct packets being transported from one device to another.
Can also connect to the Internet through a DSL, cable, or satellite modem.
Are handy because they can screen IP addresses to keep locally addressed packets within the LAN so that they are delivered without traveling a circuitous route over the Internet and back.
Monitors the IP addresses of packets on a LAN. Packets with local addresses (green) are kept within the LAN. Packets with external addresses are routed out to the Internet.
(Virtual private network) A network connection that typically carries encrypted data over the Internet to and from a remote access server.
A set of instructions embedded directly into the test of an HTML document or a file referenced from an HTML document.
(Hypertext Transfer Protocol) The communications protocol used to transmit Web pages. http:// is an identifier that appears at the beginning of Web URLs (for example, http://www.fooyong.com)
Search Engine: indexer-
The component of a search engine that review the Web pages brought back by a crawler and creates pointers to them so that they can be quickly accessed
The component of a search engine that autonomously visits Web sites collecting Web page data that will be indexed and available for searching
The component of a search engine that examines keywords entered by users and fetches results that match the query.
A word that is included in the header of an HTML document in order to describe the document's contents.
Short for electronics commerence; the business of buying and selling products online.
B2C: (business-to-consumer) individual consumers purchase goods and serves from online merchants
CSC: (consumer-to-consumer) another popular e-commerce model, in which consumers sell to each other at popular online auctions.
B2B: (business-to-business) e-commerce involves one enterprise buying goods or services from another enterprise.
B2G: (business-to-government) e-commerce aims to help businesses sell to governments.
(Simple Mail Transfer Protocol server) A computer used to send e-mail across a network or the Internet.
A small graphic on a Web page that installs cookies designed to track your online activities, also known as Clear GIF.
a situation in which one person or program successfully masquerades as another by falsifying data and thereby gaining an illegitimate advantage.
an e-mail based scam that's designed to persuade you to reveal confidential information such as your bank account number or SS#
A message sent from a Web server to a browser and stoned on a user's hard disk, usually containing information abou the user.
A group of new and innovative ways to use the Web, such as for social networking, blogging, and wikis.
Speech Recognition vs. Speech:
Speech recognition: The process by which computers recognize voice patterns and words, and then convert them to digital data
Speech Synthesis: the process by which machines, such as computers, produce sound that resembles spoken words.
Bitmap vs. Vector Graphics:
Bitmap graphics: an image, such as a digital photo, that's stored as a grid work of colored dots.
Vector graphics: An image generated from descriptions that specify the position, length, and direction in which lines and shapes are drawn.
High-Res vs. Low-Res Graphics:
Each pixel in a bitmap graphic is stored as one or more bits. The more pixels in a bitmap, the more bits needed to store the file.
A small graphic from a web page might have a resolution of 150 x 100 pixels - 150 pixels across and 100 pixels high.
High-Res graphics: contain more data rather than low-resolution graphics. With more data, it is possible to display and print high-quality images that are sharper and clearer than images produced using less data. (digital camera-1600 x 1200, photos containing 1.9 megapixels) Expensive camera 3888x2592, 10.1 megapixels aka 10 megapixel camera.
Low-Res graphics: ^
The process of superimposing a grid over a vector image and determining the color depth for each pixel
: A type of digital graphics format that displays a three-dimensional image on a two-dimensional space.
A digital rights management concept that ties access to digital content to individual subscribers, whose access can be tracked, if necessary.