Chapter 5 - Local Area Networks

File Server

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

LAN (Local Area Network)

A data communications network that connects personal computers within a very limited geographical area - usually a single building.

Packet

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

Communications Channel

A physical path or a frequency for signal transmissions.

MAN (Metropolitan Area Network)

A public high-speed network capable of voice and data transmission within a range of about 50 miles (80 km).

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.

Bluetooth

A short-range wireless network technology that's designed to make connections between two devices.

Network Attached Storage (NAS)

A storage device tat directly connects to a network.

PAN (Personal Area Network)

A term sometimes used to refer to the interconnection of personal digital devices or consumer electronics within a range of about 30 ft (10 m) and without the use of wires or cables.

Ethernet

A wired network technology that is defined by IEEE 802.3 standards.

Router

Acts as a central distribution point for getting data to its destination.

File Sharing

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

Ciphertext

An encrypted message is referred to as _______.

Plaintext

An original message - one that has not yet been encrypted - is referred to as _____.

Networked Peripheral

Any device that contains network circuitry to directly connect to a network.

Network Device

Any electronic device that broadcasts network data, boosts signals, or routes data to its destination.

Narrowband

Communications systems with less capacity.

Optic 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. (Used by MANs and WANs).

WAN (Wide Area Network)

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.

Public Folder

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

Discovery Mode

Devices equipped with Bluetooth capability can be set into __________, in which they are open for pairing. Two devices in _________ can "discover" each other and exchange passkeys. Once pairing is complete, the two devices can share data without exchanging passkeys again.

Node

Each connection point on a network is referred to as a _____.

Weak Encryption

Easy to decrypt even without the algorithm and key.

Broadband

High-bandwidth communications systems.

Strong Encryption

Loosely defined as "very difficult to break".

Microwaves

Provides another option for transporting data wirelessly.

Communications Protocol

Refers to a set of rules for efficiently transmitting data from one network node to another.

Wi-Fi

Refers to a set of wireless networking technologies defined by IEEE 802.11 standards. A _____ device transmits data as radio waves over 2.4 GHz or 5.8 GHz frequencies. ____ is compatible with Ethernet, so you can use the two technologies in a single network.

Wireless Encryption

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

RF (Radio Frequency) Signals

Sent and received by a transceiver that is equipped with an antenna.

Wireless Encryption Key

The basis for scrambling and unscrambling the data transmitted between wireless devices.

SSID (Service Set Identifier)

The name of a wireless network. In areas where there are overlapping wireless networks such as in a city or on a college campus, _____ help you log in to the right network, rather than network run by a hacker who will try to suck important information off your computer as soon as you connect.

Decryption

The reverse process - converting ciphertext into plaintext - is called _______.

Bandwidth

The transmission capacity of a communications channel.

Network Interface Card (NIC)

To connect to a LAN, a computer requires network circuitry, sometimes referred to as a _________.

Infrared Light

Today, most people are familiar with television remote controls that use __________. _________ can also carry data signals, but only for short distances and with a clear line of sight. Its most practical use seems to be for transmitting data between devices connected to a PAN.

Shared Resources

Today, the pervasiveness of LANs and other types of networks has dramatically changed the face of computing by offering _________ - hardware, software, and data made available for authorized network users to access.

Encryption

Transforms a message in such way that its contents are hidden from unauthorized readers. Designed to keep messages secret.

Handshaking

Two computers on a network might negotiate their communications protocols through a process called _____________.