Computer Internet Questions and Answers

Answer: D

Correct answer: To control network traffic entering and leaving a system according to rules

A firewall controls traffic crossing a boundary, permitting or blocking it according to a set of rules based on addresses, ports and protocols. It may be hardware, software, or both. The kinds differ in how much they examine. A packet filter looks at each packet in isolation against static rules - fast but crude. A stateful firewall tracks connections, so it can tell a reply to an outgoing request from an unsolicited incoming packet, and is considerably more secure. An application-layer firewall or proxy inspects the content of the traffic itself. What a firewall does not do is remove malware - that is antivirus software, and the second option is the usual confusion. Nor does it help against a threat that arrives by an allowed route, such as a user downloading an infected attachment. It is one layer of defence, not a complete one.

Answer: D

Correct answer: Transport

Breaking a stream of application data into pieces small enough to send, and reassembling them at the far end, is the transport layer's work - which is why its unit is called a segment.

Answer: D

Correct answer: TCP/IP

The internet protocol suite is TCP/IP - Transmission Control Protocol over Internet Protocol. The other three options are misspellings of it.

Answer: C

Correct answer: It is a type of conversation that takes place on a computer network in real time

Chat is live typed conversation: what one person types appears on the other's screen at once. A discussion area where messages are posted and read later is a forum, and uploading files is FTP.

Answer: D

Correct answer: across an interface

A protocol governs the exchange at the boundary between two entities, so the sequence of events it specifies takes place across an interface. The phrasing matters: peers communicate through an interface, and the rules apply at it.

Answer: C

Correct answer: star

A hub sits at the centre with a separate cable to each node, which is exactly the star arrangement. Logically it still behaves as a shared bus, since it repeats every signal to every port.

Answer: A

Correct answer: Crossover cable

Two devices of the same kind - switch to switch, PC to PC - need a crossover cable, which swaps the transmit and receive pairs so that each device's transmitter meets the other's receiver. A straight-through cable is for connecting unlike devices, such as PC to switch.

Answer: B

Correct answer: ATM

ATM - Asynchronous Transfer Mode - carries all traffic in fixed 53-byte cells and multiplexes them asynchronously, which is what allows voice and data to share one link with predictable delay. SONET is the transmission system such cells may travel over.

Answer: C

Correct answer: To begin a paragraph with a large dropped initial capital letter

A drop cap is an oversized first letter set into the first few lines of a paragraph, a device inherited from printing. It applies to one letter of one paragraph, not to every capital in the document.

Answer: D

Correct answer: Modem

A modem converts the computer's digital signal into a form a telephone line can carry, and converts it back at the far end - which is what the name, modulator-demodulator, records.