Computer Internet Questions and Answers

Answer: D

Correct answer: It forwards data between different networks along the best available path

A router connects different networks and forwards packets between them, choosing a path using a routing table and the destination IP address. It is what makes an internet of networks possible. The other devices in the same family operate at different layers, and the set is worth learning together. A hub repeats an incoming signal to every port indiscriminately - obsolete and wasteful. A switch forwards a frame only to the port where its destination MAC address lives, which is why switched networks are far more efficient. A repeater amplifies a signal to extend range, the second option here. A modem converts between digital and analogue for transmission over a telephone or cable line, the third. A home router usually combines several of these - router, switch, wireless access point and often modem - in one box, which is why the term is used loosely.

Answer: D

Correct answer: Google

Gmail is Google's mail service, launched in 2004.

Answer: D

Correct answer: Simplex

Simplex transmission goes one way only, as with a broadcast. Half duplex allows both directions but only one at a time, and full duplex both at once.

Answer: A

Correct answer: File server

A file server holds programs and data centrally so that every user on the LAN can reach the same copy. A print server shares a printer and a communication server shares a link, neither of which is about sharing programs and data.

Answer: D

Correct answer: Share peripherals

A LAN lets several machines use one printer or one file store. Backing up and reaching the web are possible without a local network, so neither is what the LAN itself provides.

Answer: B

Correct answer: bluesnarfing

Bluesnarfing is the unauthorised retrieval of data - contacts, messages, files - from a device over Bluetooth. It is distinguished from bluejacking, which only sends an unsolicited message and takes nothing.

Answer: C

Correct answer: Rolled

A rolled, or rollover, cable reverses the order of all eight wires and is used to reach a router or switch console port from a PC's serial port. It carries no Ethernet signalling at all, which is why neither straight-through nor crossover will do.

Answer: D

Correct answer: bits per second

Bandwidth expresses how much data a link carries in unit time, quoted in bits per second and its multiples. Note the unit is bits, not bytes, which is why a 8 Mbps connection downloads at roughly 1 megabyte per second.

Answer: B

Correct answer: Center

A page has four margins: top, bottom, left and right. There is no centre margin; centring is an alignment of text within those margins.

Answer: C

Correct answer: resource reservation protocol

Remote procedure call and internet relay chat both run at the application layer. RSVP reserves bandwidth along a path, which is a network-layer function performed by the routers rather than by an application.