CS Unit 1 CT and Network Revision

Match the following elements of the TCP/IP model

• TCP, UDP

• Internet Layer

• MAC address

  Ethernet cabling

• Link Layer

• IP

• Transport Layer

• HTTP, FTP

• Application Layer

The ​ (a)   network topology connects devices via a central ​ (b)   . The ​ (c)   topology connects devices along a ​ main cable using ​ (d)   at both ends for signal absorption. The ​ (e)   topology connects every single device physically to each other.

• switch
• terminators
• mesh
• star
• bus

Why are computers connected to a network?

​ (a)   Used to send emails and forward them between mail servers to their destination. ​ (b)   Downloads email stored on a ​ (c)   to a local client (removed after download). ​ (d)   Manages emails on a server so ​ (e)   clients can access the same email account in synchronicity.

• SMTP:
• POP3:
• remote server
• IMAP:
• multiple

What does TCP guarantee?

• delivery of data and packets delivered in the right order

• the route data will take

• fast, low latency delivery of data

• safe data without viruses

Order the steps below to show how a webpage is delivered to a browser

• URL sent to DNS server by client

• HTTP GET request issued to web server

• DNS server returns IP address of URL web server to client

• Client browser displays webpage

• Web server sends webpage data to client

​ (a)   is used in preference for other protocols such as ​ (b)   because:

a) Emails can be accessed through a browser as IMAP

doesn’t need a client application to ​ (c)   messages

b) Emails can be accessed from ​ (d)   devices because

IMAP does not ​ (e)   emails from the server

• IMAP
• SMTP
• download
• multiple
• remove

What are two methods of physical security that could be used to protect a network?

• Security cameras and motion sensors
• Firewalls and encryption
• Security guards and attack dogs
• Biometric access control

• Password entry system

The maximum data transfer rate of a network or internet connection is called:

• bit speed

• bandwidth

• cycles per second

• bus width

Reorder the following to explain how a network router works:

• Reads the destination IP address of a packet

• Looks up the next router 'hop' in a routing table

• Works out the fastest pathway to the destination IP

• Sends the data packet to the next router

• Tells other routers about any traffic issues