Computer Concepts Chapter 5

Transceiver

a combination of a transmitter and receiver. Used to send and receive data in the form of radio frequency

File server

a computer whose primary purpose it to be a repository for files that can be accessed by network workstations

Discovery mode

a device is open for pairing

File sharing

allows files containing documents, photos, music and other data to be accessed from computers other than the one which they are stored

Wireless access point

allows wireless devices to connect to a wired network

Home group

collection of trusted Windows computers that automatically share files and folders. Access to a home group could be protected a password

Optical fiber cable

composed of many strands of glass tubes that are not much wider than a human hair. Data signals speed through these tubes as rays of light

Bridge

connects two similar networks

Decryption

converting cypher text to plaintext

WAN

covers a large geographical area and usually consists of several smaller networks, which might use different computer platforms and network technologies.

Pairing

creates a persistent link between two devices, usually through the exchange of an authentication code called a passkey (used with Bluetooth)

LAN

data communication network that connects PCs within a limited geographical area-usually a single building. Uses a variety of wired and wireless technologies ex: school computer labs and home networks

RF signals

data that is broadcast and received via radio waves with a transceiver that is equipped with an antenna

Public folder

designed to hold files and folders that you want to share with other people on your network

Packet switching

divides a message into several packets that can be routed independently to their destination

Node

each connection point on a network. Usually contains a computer, networked peripheral or a network device.

Weak encryption

easy to decrypt even without the algorithm key

Circuit switching

establishes a dedicated, private link between one telephone and another for the duration of the call. It provides callers with a direct pipeline over which a stream of voice can flow

Hub

extends a wired network by adding additional ports

Repeater

extends the range of a network by restoring signals to maximum strength and retransmitting them

Strong encryption

loosely defined as very difficult to break

Router

most important network device. Acts as a central distribution point for getting data to its destination

Network interface card

network circuitry required to connect to a LAN. It's built into the main system board of most PCs.

Wireless encryption key

network security key. It's the basis for scrambling and unscrambling the data transmitted between wireless devices

WPA

offers stronger protection by making sure the packets have not been intercepted or tampered with in any way

Octet

one of the four sections of an IP address

WEP

original wireless encryption protocol. It was designed to provide a level of confidentiality similar to that of a wired network. WEP is very easy to bypass. It's a weak security measure

Packets

parcel of data that is sent across a computer network. Each packet contains the address of its sender, the destination address, a sequence number and some data

PSK

personal mode. A type of WPA used on most home networks

Communications channel

physical path or frequency or signal transmissions

Wi-Fi adapter

plugs into a USB port or an internal expansion slot

MAN

public high speed network capable of voice and data transmission within a range of about 50 miles. Ex: local internet service providers, small cable TV companies and local phone companies

Wi-Fi

refers to a set of wireless networking technologies defined by IEEE 802.11 standard. A Wi-Fi device transmits data as radio waves and it is compatible with Ethernet

Wireless encryption

scrambles the data transmitted between wireless devices and then unscrambles the data only on devices that have a valid encryption key

IP address

series of numbers used to identify a network device

Communications protocol

set of rules for efficiently transmitting data from one network noted to another

Bluetooth

short range wireless network technology that is designed to make connections between two devices

Network attached storage

storage device that directly connects to a network

MAC address

unique number assigned to a network interface cared when it is manufactured. It is used for some low level network function and can be employed to establish network security

MIMo technology

used to boost signals and spread evenly. They have 1-4 antennas.

Public key encryption

uses one key to encrypt a message and another to decrypt the message

Wireless ad-hoc protocol

wireless connection in which devices broadcast directly to each other instead of to a central access point

Wireless infrastructure protocol

wireless connections in which devices communicate through a central access point

Cryptographic key

word, number or phrase that must be known to encrypt or decrypt a message

Cryptographic algorithm

a procedure for encrypting or decrypting a message

Handshaking

a process where a protocol helps two network devices communicate

DHCP

a protocol designed to automatically distribute IP addresses

Network discovery

a setting that affects whether your computer can see other computers on a network, and whether your computer can be seen by others

RJ45 connector

a square plastic cable connector that resembles an oversized telephone connector and is used to connect Ethernet devices

Ethernet

a wired network technology that is defined by IEEE 802.3 standard, it's the dominant standard for wired connections in local area networks

Cypher text

an encrypted message

Plaintext

an original message that has not yet been encrypted

Networked peripheral

any device that contains network circuity to directly connect to a network

Infrared light

can carry data signals, but only for a short distance and with a clear line of sight. Most practical to transmit data between devices connected to a PAN

Shared resources

hardware, software and data made available for authorized network users to access

Broadband

high bandwidth communications system, such as TV and DSL

Switch

intelligently facilitates communication among multiple devices on a network

Gateway

joins two different types of networks, such as your hoe network and the Internet

PAN

refers to the interconnection of person digital devices or consumer electronics within a range of about 30 feet and without the use or wires or cables

Narrowband

systems with less capacity, such as dial-up internet

Symmetric key encryption

the key used to encrypt a message is also used to decrypt the message

SSID

the name of a wireless network. It helps you log into the right network, rather than a network run by a hacker who will try to suck important info off your computer as soon as you connect

AES

the technology used for WPA2, is one of the strongest cryptographic algorithms

Bandwidth

the transmission capacity of a communications channel. A high bandwidth communications channel can carry more data than a low bandwidth channel

Microwaves

they are electromagnetic waves with a frequency of at least 1 gigahertz; one type of channel for transmitting data over communications networks

Ethernet adapter

to make your computer Ethernet ready. Plugs into a USB port and can be used with desktops and laptops. You can also install an Ethernet card in an expansion slot

Encryption

transforms a message in such a way that its contents are hidden from unauthorized readers