AQA A-Level Computer Science 4.8 Communication and networking overview quiz quiz

Parallel transmission is physically unable to carry binary data over a cable

Serial transmission needs many more separate wires than parallel does

Parallel suffers from skew and crosstalk over distance, so serial is more reliable

Serial transmission is always slower than parallel but considerably cheaper to install

They are identical

Bit rate is signal changes per second; baud rate is bits per second

Baud rate is the range of frequencies

Bit rate is bits per second; baud rate is signal changes per second

A LAN covers a small area with owner-controlled hardware; a WAN covers a large area using third-party infrastructure

A LAN spans a very large geographic area using third-party links, whereas a WAN is always purely local to one single building

A LAN uses no networking hardware of any kind to connect its devices together

There is no real difference between the two; the terms mean the same thing

To encrypt all of the data being sent across the shared wireless radio channel for security purposes

Because devices share a radio channel and cannot reliably detect collisions, so they avoid them

To increase the maximum length allowed for the network SSID name

To speed up the raw bit rate of the wireless link

Sending all of the data as one single continuous block down a fixed dedicated circuit each time

Automatically switching off and discarding any packets that are too large

Splitting data into packets that are addressed and routed independently, then reassembled

Encrypting every single packet with one shared symmetric key

The application layer

The network (internet) layer

The link layer

The transport layer

To translate domain names into IP addresses

To host and serve the actual web pages

To encrypt all of the traffic on the link

To assign baud rates to each connected device

To encrypt all data passing between the two connected networks automatically

To control traffic between networks against rules, blocking unwanted packets

To translate human-readable domain names into addresses

To compress files before they are transmitted

It encrypts the whole web page entirely on its own, without ever needing any public key or authority at all

It hides the user's real IP address from the website they are visiting

It is issued by a trusted certificate authority and confirms a public key belongs to a stated identity

It compresses the data being sent to make the page load more quickly

It has no single point of failure that can bring the whole network down

It needs no dedicated server to be set up at all

Every device shares its resources directly with every other device

Centralised management, backup and security are easier

It defines the styling and layout

It defines the structure and content

It runs server-side database queries

It routes packets across the internet