B3 - Issues Relating To Tranmission Of Data

Question 1

What are the 4 different types of data transmission protocols?

Answer 1

Email
VOIP
Web Pages
Secure Payment Systems

Question 2

What are the 3 Email protocols?

Answer 2

SMTP - Single Mail Transfer Protocol
POP3 - Post Office Protocol 3
IMAP - Internet Message Access protocol

Question 3

What are the 3 VOIP protocols

Answer 3

SIP - Session Initiation Protocol
RTP - Real-time Transport Protocol
RTCP - RTP control protocol

Question 4

What are the 3 types of web page protocols?

Answer 4

HTTP - HyperText Transfer Protocol
HTTPS -HypeText Transfer Protocol Secure
FTP - File transfer protocol

Question 5

What are the 2 types of secure payment system protocols?

Answer 5

SET - Secure Electronic Transaction
3D secure

Question 6

What is the job of SMTP? (Email)

Answer 6

• To transmit data from your email client to outgoing mail server
• to transmit data between two outgoing mail server to recipient mail servers and reestablishes connection with outgoing mail server

Question 7

What is the job of POP 3? (EMAIL)

Answer 7

• To download emails from your mail server to email client then removed from mail server to email client then removed from mail server
• can’t access emails on multiple devices

Question 8

What is the job of IMAP? (EMAIL)

Answer 8

• receiving emails from mail server. They are synced between the client and server
• can access same emails and gets updates on multiple devices.

Question 9

What is the job of SIP (VOIP)

Answer 9

• connection between server and receiver and establish location (IP address) of people in the conversation and to agree on CODECs
• SIP packet sent from person starting VOIP call to recipient so that when the data packet is received, the phone rings

Question 10

What is the job of RTP? (VOIP)

Answer 10

• works with SIP, to transmit data packets along the connection
• takes no responsibility for receiving lost packets

Question 11

What is the job of RCTP? (VOIP)

Answer 11

• sends control packets that provide feedback on quality of data delivery
• info (E.G: bytes sent, packet courts, round trip times ( may and CODEC to boost performance)

Question 12

What is the job of HTTP? (WP)

Answer 12

• connection between client and server then transfers web pages to client so they can be presented by browser.
• when you type a URL into the browser, a HTTP message is created that requests for a file from the web server, the server sends HTTP response message containing the files requested.

Question 13

What is the job of HTTPS (WP)

Answer 13

• transmits data in encrypted format using TSL/USL

Question 14

what is the job of FTP? (WP)

Answer 14

For transferring files over the internet (E.G: uploading web pages to a web server so it can be accessed by users browsing the web)

Question 15

What is the job of SET? (SPS)

Answer 15

• communication protocol when purchase process is started only purchase the order and it is sent to the website , card details go to merchant bank. Payment is authorized with purchasers bank. Authorization is retuned to the computer website

Question 16

What is the job of 3D Secure? (SPS)

Answer 16

• XML protocol, uses SSL encryption to ensure data is secure
• merchant website will check of card is on 3D secure. If so, the buyer will be directed to a 3D Secure page for their own bank to authenticate the buyer (natwest verification at the end of buying something)

Question 17

What are the two connections of web page protocols?

Answer 17

1. Control connection = to administrate the connection and send commands
2. Data connection = to transfer files between the client computer and the server

Question 18

What are the two security issues of data transmission?

Answer 18

Sniffing and spoofing

Question 19

What is sniffing?

Answer 19

• to gain unauthorized access to data
• packet sniffer : instructs your computer to inspect all data transmitted over a network (pw, credit card details)
• Public Wifi and Bluetooth vulnerable (harder if it’s wired)

Question 20

What is spoofing?

Answer 20

• when you get your computer to pretend to be another computer
• using fake credentials and preventing them to the network to access to services meant for another device (confidential data)
• spoofing to perform denial of service attack by spoofing IP address

Question 21

What are the two security prevention methods?

Answer 21

Firewalls and encryption

Question 22

What is a firewall?

Answer 22

• hardware/software firewalls to monitor traffic and block anything that appears to be dangerous/fake
• block access to certain websites, prevent certain data being sent out of business .
• prevent external computer accessing internal computer, closing certain ports to prevent network traffic going through them (built into router - uses rules to filter traffic and prevent anything unwanted
• hardware firewall can prevent a Denial Of Service attack

Question 23

What is Encryption?

Answer 23

• Prevents unauthorized here from reading intercepted data
• SSL- encrypts the data to secure it so it can’t be accessed by anyone without encryption key
• it relies on SSL/ digital certificates to authenticate a user and allows them to use public key infrastructure

Question 24

What is bandwidth ,latency and ping?

Answer 24

Bandwidth - amount of data that can be transferred from one computer to another in a given time (bits per second) (the higher bandwidth the better)
Latency - time taken for a data packet to transfer over a network (Ms) (the lower latency the better)
ping - time taken for a data packet to travel over a network to destination and back to you

Question 25

What is compression and the two types of compression?

Answer 25

The downsizing of a file so less bandwidth is needed to share Lossy and lossless

Question 26

What is lossy compression?

Answer 26

Permanently deletes certain bits of data and it can’t be decompressed

Question 27

What is lossless compression?

Answer 27

Uses algorithms to pack data into a smaller space

Question 28

Advantages of lossy compression?

Answer 28

Has a smaller file size than lossless so the upload and download times are quicker

Question 29

Disadvantages of lossy compression?

Answer 29

- Worse quality and can’t be restored to original quality (printing/assessment - quality is important) - Video compression uses CODEC which person receiving may not have installed ( can’t watch it ) - Sometimes files can’t be compressed further so compressing = larger file size

Question 30

Advantages of lossless compression

Answer 30

Can be decompressed to original (can share)

Question 31

Disadvantages of lossless compression?

Answer 31

- Compressed files can be incorrectly identified as malware by antivirus software and block it - file archive compression formats only work with specific archive software (recipient software must be compatible) - decompressing = higher processing time - may increase file size if it can’t be compressed more.

Question 32

What is a feature of CODECs and the two types of CODECS?

Answer 32

Because there’s so many, you must have the same CODEC the data is coded with to decode it. The two types are software and hardware CODECs

Question 33

What is the job of hardware CODECs?

Answer 33

- to encode analogue data ( computer can’t store/ use ) into digital and vice versa. EG: microphone VOIP transmits voice so it can be heard on computer

Question 34

What is the job of software CODECs

Answer 34

For audio and video data to compress so it can be transmitted over network to send data quickly (VOIP for real time convo) Lowers buffering