Chapter 6 Flashcards

1
Q

LAN

A

A collection of computers and peripheral devices connected together within a single site.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

WAN

A

A collection of computers and LANs connected together over a geographically remote area, using leased infrastructure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Topology

A

A description of how devices are connected together. Does not necessarily represent physical layout.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Bus

A

A topology where each device is connected to a main cable, referred to as the bus. Any device can transmit at any time but only one transmission can occur on the main bus at any one time.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Ring

A

A topology where each device is connected to the next in a loop. Uses a tokenpassingprotocol to allow transmission by one device at a time.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Star

A

A topology where each device has its own cable connecting it to a central device, which can be a switch or a server.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Peer-to-Peer

A

A method of organising devices in a network where devices are all of equal status rather than having specialised roles. Each computer can access resources on another computer, assuming access rights have been granted by the other computer.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Client-Server

A

A method of organising devices in a network where some computers havespecialised roles: servers. The servers provide resources and services to the other computers, known as clients. Management of the network and shared resources/files is centralised at the server.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Hub

A

A hardware device that provides connectivity to a LAN cable. A multiport box that has a connection to the LAN from one side and several computers on the other. Can be wireless or cabled.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Switch

A

A hardware device that is similar to a hub but it has built-in intelligence to direct traffic to the right place. Computers connected to a switch form a star topology LAN.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Wireless Access Point

A

The device to which a computer connects wirelessly. Can be a wireless hub or awireless switch.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

NIC

A

Network Interface Card: the card that plugs into a computer to provide a connection to a LAN. Can be wireless or cabled. Holds the MAC address.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

MAC Address

A

A unique hardware number allocated to every NIC. It is a 48-bit address, usually written in hex, e.g. 00-09-7C-F1-F7-85

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Message

A

A communication between devices. Split into packets for sending over a networkand put back together again at the other end.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Packet

A

A fixed size chunk of a message created to send a message over a network. Ithas its own header containing data such as the destination address and packet number (so the message can be put back together in the right order).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Protocol

A

A set of rules that defi nes how devices communicate. E.g. IP, HTTP, HTTPS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Internet

A

A public worldwide network where computers and networks in geographicallyseparate locations are connected together using a variety of communication links.Devices communicate using Internet Protocol (IP).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Routers

A

The hardware devices that make up the backbone of the Internet as well as (smaller ones) providing connectivity from a LAN to the Internet. Use Internet Protocol to communicate with each other.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Modem

A

The hardware device used to convert the digital transmission from a computerinto an analogue signal that can be carried over the analogue telephone network.A method of accessing the Internet.

20
Q

Digital

A

A transmission signal that is made up of separate values (numbers), as opposed tothe continuously changing signal in analogue transmissions.

21
Q

Analogue

A

A transmission signal that is continuously changing, as opposed to being made upof separate values (numbers). Sound in the real world is analogue.

22
Q

Broadband

A

A digital method of connecting to the Internet that allows more than one transmission at the same time, e.g: phone and computers. It may use the site’snormal phone line or a fibre optic cable to carry transmissions.

23
Q

WWW

A

World-Wide Web: a collection of pages distributed on servers connected to theInternet. Uses HTTP to request and send pages to browsers.

24
Q

HTTP

A

HyperText Transfer Protocol: the protocol used by a browser to send page requeststo a server and also by the server to send back the required page.

25
Q

HTTPS

A

A secure version of HTTP where transmissions are encrypted.

26
Q

IP Addressing

A

A method of labeling any device connected to the network with a uniquenumerical value. Uses four bytes usually expressed in this notation: 123.123.003.243

27
Q

Domain Name

A

The text label for a website in the Internet: www.bbc.co.uk It corresponds to an IP address for that site.

28
Q

DNS Servers

A

Domain Name System server: a database of domain names and associated IP addresses stored on servers. There are many DNS servers distributed across the Internet, which communicate with each other.

29
Q

HTML

A

HyperText Markup Language: the programming language used to define the layout and content of a webpage. Uses tags in conjunction with a CSS to control how content is displayed.

30
Q

CSS

A

Cascading Style Sheet: defines the formatting and layout of the content defi ned by the HTML code. E.g. may be 32pt Arial in Green.

31
Q

Tags

A

Labels that go around the content (text, pictures etc) to define the page layout.Eg: A heading

32
Q

User Access Levels

A

A network policy that defines which users can see which folders and files and the type of access they have to them. Eg: Read-Only or Read-Write.

33
Q

Encryption

A

Where the data is changed, using a key, before it is transmitted so that it canonly be deciphered by another device with the appropriate key. To anyoneintercepting the message it would be unintelligible.

34
Q

Acceptable Use Policy

A

An agreement that computer users will sign/agree to before being allowed access to a computer or the network.

35
Q

Failover

A

When a hardware component fails, the computer switches over to a redundantcomponent without the service to the user being interrupted.

36
Q

Redundant

A

Spare, ready to be used if another component fails. Relates to spare hardwarecomponents in fault-tolerant systems that use failover.

37
Q

Fault-Tolerant

A

A system that has been designed to cope with hardware failures. Usesredundant hardware and failover usually.

38
Q

Backup

A

A copy of data is taken from a live computer system as a precaution against system failure or corruption/deletion of individual files/folders. To be restored in the event of data loss.

39
Q

Archiving

A

Files are removed from the main computer system but kept in long-term storage, just in case they are needed in the future or because the law requires they be kept. Creates space on main system.

40
Q

Disaster Recovery

A

A collection of precautions that ensures the computer system can be reestablished very quickly after a catastrophe. Includes backup policy, complete hardware system available offsite at short notice and policies to restore data and applications on the replacement hardware.

41
Q

Compression

A

Making files smaller for quicker transmission over a network.

42
Q

Lossless compression

A

File is compressed with no loss of essential data.

43
Q

Lossy compression

A

Files are compressed by removing some data that is less essential for the purpose. For example, using fewer colours in a picture (reduce colour depth).

44
Q

What is an IP address?

A

A unique identifier which consists of 4 8-bit numbers

45
Q

What is a MAC address?

A

Every computer today has some sort of Network Interface Card (NIC). Every NIC is created with a hardware number permanently “burned” into it. This permanent hardware number of known as the MAC (Media Access Control). MAC addresses are 48 bits in length and usually displayed as a 12 digit hexadecimal number.

46
Q

What is a packet?

A

A packet is one unit of binary data capable of being routed through a computer network.