The Internet

Front 1

What is the internet?

Back 1

It is a network of networks set up to allow computers to communicate to each other globally.

Front 2

What is a Uniform Resource Locator (URL) ?

Back 2

It is the full address for an internet resource. It specifies the location of a resource on the internet, including the name and usually the file type so that a browser can go and request it from the website server.

Front 3

What does a URL contain?

Back 3

Method, Host, Location, Resource

Front 4

Why do we need Internet Registrar/Registraries?

Back 4

To ensure that a particular domain name is only used by one organisation.

Front 5

What is the purpose of a Domain Name?

Back 5

It identifies the area or domain that an internet resource is located in. (eg: .co.UK is in the UK)

Front 6

What is a Fuly Qualified Domain Name? (FQDN)

Back 6

It is one that includes the host server name (eg: WWW, FTP...)

Front 7

What is an Internet Protocol? (IP)

Back 7

An IP address is a 4 byte number that indicates where a packet of data is to be sent or where it has been sent from.

Front 8

What is an Internet Protocol address? (IP address)

Back 8

An IP address is a 4 byte number that indicates where a packet of data is to be sent or where it has been sent from.

Front 9

What is Packet Switching?

Back 9

It is a method of communicating packets of data across a network on which other similar communications are happening simultaneously.

Front 10

What is Packet Switching?

Back 10

It is a method of communicating packets of data across a network on which other similar communications are happening simultaneously.

Front 11

What does a data packet consist of?

Back 11

Header, Payload and Trailer.

Front 12

What is in the header of a packet?

Back 12

IP's and Packet Sequence number.

Front 13

What is in the trailer of a packet?

Back 13

Error checking

Front 14

What are Routers used for?

Back 14

To connect at least 2 networks, commonly 2 LANs together.

Front 15

What are Routers used for?

Back 15

To connect at least 2 networks, commonly 2 LANs together.

Front 16

What is the job of a Router?

Back 16

To read the IP address in each packet and forward it on to the destination via the fastest and least congested route to the next router, then repeat.

Front 17

What is the job of a Router?

Back 17

To read the IP address in each packet and forward it on to the destination via the fastest and least congested route to the next router, then repeat.

Front 18

What is the job of a Router?

Back 18

To read the IP address in each packet and forward it on to the destination via the fastest and least congested route to the next router, then repeat.

Front 19

What is a firewall?

Back 19

It is a security checkpoint designed to prevent unauthorised access between 2 networks. A router may contain a firwall.

Front 20

What does Packet Filtering do?

Back 20

It controls network access according to network administrator rules by examining the source and destination IP addresses in packet headers. If the IP addresses match the whitelist they are allowed in.

Front 21

What does a proxy server do?

Back 21

It intercepts all packets entering and leaving the network, hiding the true network addresses of the source from the sender. This enables privacy and anonymous surfing.

Front 22

What is Encryption?

Back 22

It is the process of scrambling data so that it becomes very difficult to unscramble and interpret without the correct key.

Front 23

What is Symmetric Encryption?

Back 23

It is when you use the same key to encrypt and decrypt data. This means the key must be sent with the data which causes obvious security risks.

Front 24

What is Asymmetric (Public Key) Encryption?

Back 24

It uses 2 different seperate but related keys. One key, known as the public key is made public so that others wishing to send you data can use this to encrypt it. Only your private key (only known by you) can decrypt the data.

Front 25

What is a Digital Signature?

Back 25

It is the equivalent of a handwritten signature or security stamp but offers even greater security

Front 26

What is the process of a Digital Signature?

Back 26

1) A mathmatical value is created from the unencrypted data (hash total/checksum). This means any change in the message changes the Hash Total.

2) Sender uses their private key to encrypt the hash total and the whole message is encrypted by the recievers public key.

3) Decrypts using the other keys then compares the Hash total produced with the one total in the digital signature. If the same, the message has not been intercepted

Front 27

What is the process of a Digital Signature? (3 steps)

Back 27

1) A mathmatical value is created from the unencrypted data (hash total/checksum). This means any change in the message changes the Hash Total.

2) Sender uses their private key to encrypt the hash total and the whole message is encrypted by the recievers public key.

3) Decrypts using the other keys then compares the Hash total produced with the one total in the digital signature. If the same, the message has not been intercepted

Front 28

Worms, Trojans and Viruses are part of what type of software?

Back 28

Malware / Malicious Software

Front 29

What is Malware / Malicious Software designed to do?

Back 29

To cause inconvenience and loss or damage to programs, data or computer systems.

Front 30

What is a Transmission Control Protocol / Internet Protocol? (TCP/IP)

Back 30

It is a set of networking protocols that work together as 4 connected layers, passing incoming and outgoing data packets up and down the layers of network communication.

Front 31

What are the 4 layers of the TCP/IP?

Back 31

1) Application Layer

2) Transport Layer

3) Network Layer

4) Link Layer

Front 32

What are the 4 layers of the TCP/IP?

Back 32

1) Application Layer

2) Transport Layer

3) Network Layer

4) Link Layer

Front 33

What is the Application Layer used for?

Back 33

It uses protocols relating to the application being used to transmit the data.

Front 34

What is the Transport Layer used for?

Back 34

It uses the TCP to establish an end to end connection with the recievers computer. The data gets split into packets and labelled with a number, the total packets and the port number.

Front 35

What does the port number do?

Back 35

It determines which application may deal with a data packet as it enters your computer.

Front 36

What is the Network Layer used for?

Back 36

It adds the source and destination IP addresses to the packets.

Front 37

What is the Link Layer used for?

Back 37

It is the physical connection between network nodes and adds the unique Media Access Control (MAC) addresses identifying the Network Interface Cards (NIC) of the source and destination devices. This means that once the packet finds the correct network via the IP, it can locate the correct piece of hardware (eg pc, phone etc).

Front 38

What is a MAC Address?

Back 38

A unique 12-digit hexadecimal code that is hardcoded on every Network Interface Card during manufacture. This identifies a particular printer phone, pc etc anywhere in the world so that data packets can be routed to them.

Front 39

What does the FTP do?

Back 39

It is used to efficiently transfer data across a network, often the internet.

Front 40

What is Secure Shell (SSH) used for?

Back 40

It is used to remotely access and manage a computer from another device.

Front 41

What is Secure Shell (SSH) used for?

Back 41

It is used to remotely access and manage a computer from another device.

Front 42

What does a Web Server do?

Back 42

It hosts a website and handles client requests, typically through HTTP to send content to users wanting to view pages of the site.

Front 43

3 Advantages of a Thin-Client.

Back 43

1) Easy to set up, maintain and add terminals.

2) Software and updates can be installed on server and automatically distributed to each client terminal.

3) More secure as data is all kept centurally in 1 place.

Front 44

4 disadvantages of Thin-Clients.

Back 44

1) Reliant on the server.

2) Requires a very powerful and reliable server which is expensive.

3) Server demand and bandwidth increased.

4) Consumes more power.

Front 45

3 advantages of Thick-Clients.

Back 45

1) Reliable providing more uptime.

2) Can operate without a continuous connection to the server.

3) Better for running more powerful software applications.

Front 46

3 disadvantages of Thick-Clients.

Back 46

1) More expensive, higher spec pcs required.

2) Installation of software required on each terminal seperately.

3) Integrity issues with distributed data.

Front 47

What is Thick-Client Computing?

Back 47

The Thickness of a client computer refers to the level of processing and storage that it does compared with the server it is connected to. The more processing the server does, the thinner the client becomes.