Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

CCEA A2 Digital Technology > U1T1.1 - Networks > Flashcards

U1T1.1 - Networks Flashcards

Network Resources, Protocols, Transmission Media + Error Detection + Correction

1
Q

What is a network?

A

A number of cable/wirelessly linked computers. Can share resources + communicate.

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

What is a LAN?

A

Local Area Network. Computer systems close (same building) Can directly physically connect. Normally connected with wire cables, wireless links or fibre optic.

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

What is a MAN?

A

Metropolitan Area Network. Covers highly populated area less than 30 miles. Uses fibre optic cable + wireless. Cost effective as users close.

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

What is a WAN?

A

Wide Area Network. Computers spread far. Use phone links, fibre optic + satellite. May links LANs in large spread organisation.

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

What is an NIC?

A

Network Interface Card. Electronic circuit board in computer to connect to network, wired or wireless if WNIC. Allows communication with file server + other network computers. Provides port to allow network cable to attach to NIC. Has various speeds.

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

What is a WNIC?

A

Wireless Network Interface Card. On most laptops to connect to wireless router (using Wi-Fi) to access network.

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

What is a server?

A

Computer on network managing resources that can be used by any authorised client station. Manages resources. Only perform their specific server tasks. Files secured by username + password + firewall.

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

What are 9 different types of server?

A

File, printer, CD-ROM, database, internet. web, application, terminal services + mail.

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

What is a switched hub?

A

Single connection point for comps on network. Allows many computers to connect to it directly with network cables. Checks destination of data packet + ensures it’s forwarded to intended comp. Most also support load balancing so data packets transmitted via diff network segments based on traffic patterns.

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

What is a repeater?

A

Network device used in transmission of data when signal is distorted due to long distance. Regenerates/boosts digital signals which have been attenuated so can be transmitted longer distances.

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

What is a WAP?

A

Wireless Access Point. Wireless computer networking device. Allows Wi-Fi enabled device to connect to router to access network. Wi-Fi hotspots use WAP to support Wi-Fi coverage area. Connect wireless devices to wired network using Wi-Fi/Bluetooth. Creates hotspot.

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

What is a media converter?

A

Allows 2 dissimilar media types to connect. Changes physical signals where diff network types link (fibre optic + copper)

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

What is an IP address?

A

Internet Protocol Address. Devices which communicate using internet are assigned these unique codes. Consists of 32 bits in 4 octets of nums from 0 - 255 in decimal form. e.g. 134.213.246.167 Static (perm) or dynamic (temp). Provided by ISP. Changes based on location.

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

What do networks using TCP/IP protocol use to route messages?

A

IP address of destination.

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

What is a MAC address?

A

Media Access Control Address. Allocated to NIC when it’s made. Unique to each node, provided by manufacturer. Made of 6 2 digit hexadecimal nums, separated by colons. Automatically recognised by most networks + not required by user. e.g. 0a:1d:8f:b1:c0:8e. Used in filtering process on wireless networks to track users + limit access. May only accept certain MAC addresses.

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

What does a file server do?

A

Provides central disk storage for network users. Software identifies each user’s files to make them inaccessible to others. Can access files from any client station or with suitable access rights, other users’ data.

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

What does a printer server do?

A

Allows client stations to use printers controlled by it. Provides facilities of printer spooler.

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

What does a CD-ROM server do?

A

Allows all client stations to obtain data from CD-ROM being used by CD-ROM server computer. Has access to many disks from collection of several drivers, CD jukebox or disk images on server.

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

What does a database server do?

A

Manages large database. Client stations can access data in it + can maintain it if authorised. Server carries out database processing.. Query sent by client + results assembled by server + returned. Ensures database consistency.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What does an internet server do?

A

Manages internet access for all network users. Often called proxy server as combines additional safety features of proxy server.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does a web server do?

A

Provides internet pages for other comps through internet. Provides cache of web pages stored when first accessed so supplied without accessing internet next time so no delay.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What does an application server do?

A

Stores app software (word processor program) When needing to use, temporarily copied from server so easy to update software centrally + monitor usage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What does a terminal services server do?

A

Stores + runs app software over network for client stations. Software not copied.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What does a mail server do?

A

Manages email for network. Provides email addresses, stores incoming emails until collected by users + sends outgoing emails to destinations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is IP?

A

Internet Protocol. Standard set of rules to ensure proper info transfer between comps on internet. IPs determine how data is to be structures + control signals used.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are some types of IPs?

A

HTTP, SMTP + POP3.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is HTTP?

A

HyperText Transfer Protocol. Defines process of identifying, requesting + transferring multimedia web pages over internet. Web pages usually constructed using HTML.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is SMTP?

A

Simple Mail Transfer Protocol. Transfer email between comp systems. Incoming mail stored on service provider’s comp. Doesn’t automatically download mail once user connects to server but requires specific request to do so.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is POP3?

A

Post Office Protocol 3. Defines email transfer between comp systems. Provides more facilities than SMTP.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is P2P?

A

Peer to Peer Networking. Alt to client-server networks. All comps on network are equal. Allows hardware + software to function without dedicated servers. Each comp is resource supplier + consumer. Make some resources (processing power/disk storage) available to other comp + can request resource from them. Each node in charge of own security + admin + decides on other access to their resources. Cheaper installation as no dedicated server.

31
Q

Give 1 disadvantage of P2P.

A

Data not centrally organised or controlled leading to duplicated + errors. Security not centrally controlled so less secure.

32
Q

Describe the role of a fileserver in a client server network.

A

File storage, file backup, provides app software + printer management. All comps connected to it via switch/hub. Must log in (username + pass) on client comp to access server. Same resources on each client (printers, app software, data storage). Files can be read only or read/write access.

33
Q

Give 1 disadvantage of a client server network.

A

Reliance on 1 central comp can cause issues when it crashes.

34
Q

What are 4 characteristics of clients?

A

Initiates requests for data from server. (email)
Waits for server responses + acts on it (download + display)
May simultaneously contact several servers (web browser w/ multiple web servers)
Hides data request complexity from users (presents received data, not communication details)

35
Q

What are 4 characteristics of servers?

A

Waits for client to request data.
Process client request + reply (data sent)
Connection from multiple clients at same time (web servers to thousands of clients)
Doesn’t interact with end user (client is intermediary)

36
Q

What are the benefits of client server networks?

A

Central backing store for all users, software centrally held + shared, faster. User IDs, passwords + access levels controlled by central computer, servers physically located in secure office. Backup centralised + regular. Can support many users + expand.

37
Q

What are the disadvantages of client server networks?

A

If central comp down, all users affected. More expensive + complicated.

38
Q

What are the benefits of p2p networks?

A

SImpler, cheaper, no special network operating systems required.

39
Q

What are the disadvantages of p2p networks?

A

Storage facilities distributed so hard to remember which files of which comp. Software copies on individual software. Security not centrally controlled so multiple passwords for diff resources. Backup individual comp user responsibility. No central comp so when shared resource (printer) used, drop in performance where resource resides. Best with less than 10 users.

40
Q

What is a bus network?

A

All nodes connected to backbone. 1 terminator at each end. Data transmitted both directions. If one node is down, network still works. Easy to add nodes. More nodes makes slower. When multiple nodes send messages at same time, collisions can occur.

41
Q

How are collisions avoided in a bus network?

A

Before sending message, each node checks whether backbone is busy + waits if so. If collision occurs, node re-transmits message later. This protocol is know as CSMA/CD.

42
Q

What is a star network?

A

Each node connected to central node (fileserver/hub/switch) by own cable. Host comp controls all comms on network. If host down, whole network fails. Each node has own connection so no contention for pathways. If node fails, network still works. Adding a new node easy (scalable). Few collisions. Good security as all nodes have to interact with server first. Expensive due to cables, if server fails, all fails. Need high performance switch/server due to all traffic going through it.

43
Q

What is a ring network?

A

Each node connected to 2 adjacent nodes, no fileserver. Token passed from node to node. When node has token, it can add message data to network which is passed until it arrives at destination. Data travels in 1 direction so no collisions. Hard to add new nodes as existing cable must be severed and join to either end of new node. Broken connection causes total failure unless node can be isolated. With long distances, signal degenerates (fixed with repeater)

44
Q

What are the 3 main LAN topologies?

A

Bus, ring + star.

45
Q

What is a token?

A

Messenger/postman in a ring network which picks up messages and takes them to destination specified.

46
Q

What is a communication protocol?

A

Set of rules/procedures that enable devices on comp networks using diff technologies/from diff manufacturers to communicate. Formal descriptions of digital message formats + rules. Necessary to exchange messages in/between computing systems + needed in telecomms. Comp networks can’t exist without them.

47
Q

What do communication protocols cover?

A

Authentication, error detection + correction + signalling.

48
Q

Where are communication protocols implemented?

A

Hardware + software. Used everywhere in analogue + digital comms. Comp networks can’t exist without them.

49
Q

Why are protocols needed?

A

Allows devices from diff manufacturers with diff character sets and transmission speeds to communicate using set rules.

50
Q

What does a network protocol do?

A

Defines rules + conventions for comms between network devices + include mechanisms for devices to identify + make connections with each other, as well as formatting rules that specify how data is packaged into messages sent + received.

51
Q

What is OSI?

A

Open Systems Interconnection. It provides a framework for data to be transferred between networked comps. Works even if diff data formats/types of networks are communicating. Basic model of networking. Set of specific protocols.

52
Q

What is the core of OSI?

A

OSI reference model. A set of 7 layers which define the diff stages data must go through to travel from 1 device to another over a network.

53
Q

Who developed the OSI model?

A

The International Standards Organisation (ISO). It was developed as guidelines for developing standards. Means easier connection to other manufacturers.

54
Q

What are the 7 layers of OSI? (group them)

A

Application Set (Application, Presentation, Session) + Transport Set (Transport, Network, Data Link, Physical)

55
Q

What are the benefits of OSI?

A

Any hard/software meeting OSI standard can communicate with any other hard/software also meeting standard, consumers given wide choice since it all works together + not dependent on OS used + protocols for it are defined at each stage. Also error handling in each layer + diff layers can operate automatically.

56
Q

What is the application set concerned with?

A

Controlling how various apps currently running make use of network.

57
Q

What is the transport set concerned with?

A

Passing info through network, no matter where info comes from.

58
Q

What is the basic rule of OSI?

A

Each layer can only talk to the layer above or below it.

59
Q

Describe the application layer.

A

Concerned with presenting info in human friendly way to the end user. Receives info from presentation layer. Deals with data transfer.

60
Q

How does info pass through OSI?

A

On way out, it goes from application to physical. On way in, it comes from physical to application.

61
Q

Describe the presentation layer.

A

Takes data from application layer + converts into standard format which other layers understand. It also implements encryption/decryption and may compress/decompress info.

62
Q

Describe the session layer.

A

It establishes, maintain + ends comm with receiving device. Opens temp channel between 2 devices to allow comms. Can have 1+ session running at once.

63
Q

When does a session begin in terms of networking?

A

When an application wants to connect to a remote server (WAN)

64
Q

Describe the transport layer.

A

Maintains data flow, checks errors + recovers data. Flow control means it looks to see if data is coming from multiple applications + integrates each’s data into single stream for physical network. Divides info into convenient sized packets which will be sent on diff routes to destination. May arrive in diff order to that they were sent in and are reassembled at destination in true order.

65
Q

Describe the network layer.

A

Determines route data is sent to recipient. Addresses logical protocols, routing + addressing. ‘Traffic policeman’ of OSI. Adds correct IP address to each packet + reads incoming addresses, allowing through if they are for the current comp. Packets not addressed are blocked (firewall)

66
Q

Describe the data link layer.

A

Appropriate physical protocol assigned to data, network type + packet sequencing defined. Converts packets of data into series of bits + incoming into complete packets. Bits may be flipped/corrupted so attempts to fix these also. (parity bit checking) Involved in error checking + correction. Communicates with network + physical layers.

67
Q

Describe the physical layer.

A

Level of actual hardware. Defines physical characteristics of network (connections, voltage levels + timing). Converts bits + bytes info physical effect. e.g. light pulse/radio wave

68
Q

What is a network topology?

A

Describes layout + config of devices in comp network.

69
Q

What is a node?

A

Device connected to network. PC, printer, server etc.

70
Q

What are 3 advantages of network compared to standalone computers?

A

Share resources (printers), file sharing easy as goes into shared area, can be regarded as read only if wanted, centrally controlled so data safer with firewall, usernames + passwords.

71
Q

What are the main features of a client server network?

A

Central hub, client is node (usually PC), requests resources (web access). Server replies to command and hands out resources. Server controls security across network.

72
Q

Compare + contrast p2p + served based networks?

A

In p2p; nodes manage own resources, nodes have equal status, upgrades managed independently on each node.
In server; server shares resources, nodes request resources, remote software upgrades possible.

73
Q

Compare the ring topology with the star topology in terms of security.

A

Ring less secure as data sent from node to node until it reaches intended recipient whilst in star, data sent directly to intended recipient.

CCEA A2 Digital Technology (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions