Computer Internet Questions and Answers

Answer: B

Correct answer: personal area network

Bluetooth is a short-range technology, reaching a few metres, and is defined as a personal area network standard - the space around one person and the devices they carry.

Answer: D

Correct answer: The maximum rate at which data can be transferred

Bandwidth is the maximum rate at which data can be carried, measured in bits per second - Mbps or Gbps. It is a measure of capacity, not of speed in the everyday sense. It should be distinguished from two related quantities that users often conflate with it. Latency is the delay before data begins to arrive, measured in milliseconds; a satellite link may have high bandwidth and terrible latency, which is why it is poor for video calls but fine for downloads. Throughput is the rate actually achieved, which is always less than the bandwidth because of protocol overhead, congestion and retransmission. The analogy usually offered is a pipe: bandwidth is its width, latency is the time for water to travel its length, and throughput is what actually comes out. Note the unit trap: network speeds are quoted in bits per second and file sizes in bytes, so a 100 Mbps link transfers about 12.5 MB per second.

Answer: A

Correct answer: Delivering computing services over the internet rather than from local hardware

Cloud computing delivers computing resources - servers, storage, databases, software - over the internet from a provider’s data centres, rather than from hardware the user owns and maintains. Its three service models are worth knowing. IaaS supplies raw infrastructure, virtual machines and storage, leaving the operating system and everything above to the customer. PaaS supplies a platform on which to run applications without managing the servers. SaaS supplies finished software over the web - Gmail and Google Docs are examples. The deployment models are public, private, hybrid and community. The attraction is that capacity can be added and removed on demand and paid for by use, turning a capital cost into an operating one and removing the need to size hardware for peak load. The concerns are dependence on a provider, the difficulty of moving between them, and the legal question of where data physically resides.

Answer: A

Correct answer: Wireless network

Wi-Fi is the trade name for wireless local networking over the IEEE 802.11 standards. The name suggests wireless fidelity but was coined as a brand rather than as an abbreviation.

Answer: D

Correct answer: A network covering a small area such as an office or building

A LAN, or Local Area Network, connects devices within a small area - a room, a building, a campus - typically over Ethernet cable or Wi-Fi, and typically owned and administered by one organisation. The classification by geographic scale runs: PAN for a personal area of a few metres, as with Bluetooth; LAN for a building or campus; MAN for a metropolitan area such as a city; and WAN for anything larger, of which the internet is the largest example. The differences are not only of size. A LAN has high bandwidth, low latency and low error rates because the distances are short and the medium is owned; a WAN uses leased lines or public infrastructure and is slower and less reliable in proportion. A VPN creates an encrypted tunnel across a public network so that a remote device behaves as though it were on a private LAN.

Answer: A

Correct answer: network layer

Choosing the path a packet takes across an internetwork is the network layer's function, which is why routers are layer 3 devices. The data link layer moves frames across a single link only.

Answer: B

Correct answer: Format a main document

The merge process is: identify the main document, prepare the data source, insert the merge fields, preview the result and complete the merge. Formatting the main document is ordinary editing and is not one of the steps the wizard defines.

Answer: C

Correct answer: https

A URL breaks into recognisable parts, and https before the colon is the scheme or protocol - it says how the resource is to be fetched. The rest divides as follows. www is a subdomain, a conventional but entirely optional label. example.com is the domain name, of which .com is the top-level domain. /page.html is the path to the resource on that server. A URL may also carry a port after a colon, a query string after a question mark, and a fragment after a hash - the fragment being handled by the browser alone and never sent to the server. Other schemes exist besides http and https: ftp for file transfer, mailto for an email address, and file for a local file. URL stands for Uniform Resource Locator.

Answer: A

Correct answer: World wide web

WWW stands for the World Wide Web - the system of linked hypertext documents carried over the internet, which is the network beneath it.

Answer: B

Correct answer: A small piece of data a website stores in the browser

A cookie is a small piece of data a site asks the browser to store and to send back with every subsequent request to that site. It exists because HTTP is stateless: the server remembers nothing between requests, so a cookie is what allows it to recognise a returning visitor. That is how a login persists, how a shopping basket survives navigation, and how preferences are remembered. They are classified in useful ways. A session cookie lasts until the browser closes; a persistent one has an expiry date. A first-party cookie belongs to the site being visited; a third-party cookie belongs to another domain embedded in the page, which is what allows advertisers to track a user across sites - and what privacy regulation such as the GDPR addresses. A cookie is inert data, not a program, so it cannot itself be a virus.