ICT Fundamentals for Libraries Questions and Answers

Answer: A

The layer between the Physical and Network layers is the Data link layer.

The seven OSI layers, from the bottom: 1 Physical, 2 Data link, 3 Network, 4 Transport, 5 Session, 6 Presentation, 7 Application. The Data link layer packs bits into frames, adds physical (MAC) addresses and checks for transmission errors on a single link, before the Network layer routes packets between networks.

The Transport layer (4) sits above the Network layer, and the Session (5) and Presentation (6) layers are higher still, so none of them lies between layers 1 and 3.

Answer: B

The ones that are not Web 2.0 tools are ontologies and the intelligent web, so the answer is (i) and (iii) are correct.

Ontologies and machine-understandable, 'intelligent' web services belong to the Semantic Web, often called Web 3.0, which aims to let software reason over the meaning of data.

Facebook (a social networking site) and RSS feeds (syndication of new content) are standard Web 2.0 tools, built on user participation and sharing, so codes containing (ii) or (iv) are wrong.

Answer: C

The order is (ii), (iv), (i), (iii): Physical, Data link, Network, Transport.

In the OSI model the layers are numbered from the bottom: 1 Physical, 2 Data link, 3 Network, 4 Transport, 5 Session, 6 Presentation, 7 Application. Data being sent out pass down the layers and data being received pass up them, and the conventional numbering sequence starts from the Physical layer.

The other codes break this order: they put the Transport or Network layer first, or place the Physical layer after the Data link layer, which cannot be, since the Data link layer frames the bits the Physical layer carries.

Answer: C

The two that are not features of ISDN are (iii) and (iv), so the answer is (iii) and (iv) are correct.

ISDN, the Integrated Services Digital Network, is a set of communication standards (ii) for simultaneous digital transmission (i) of voice, data and video over the ordinary telephone network, for example on two 64 kbps B channels at once.

Creating and combining packets (iii) describes a packet assembler/disassembler on a packet-switched network such as X.25, whereas ISDN is basically circuit-switched. A program to visit web pages (iv) is a web browser, software rather than a network standard. So codes including (i) or (ii) are wrong.

Answer: D

The topology with the highest reliability is Mesh Topology.

In a full mesh every node has a dedicated link to every other node. If one link or node fails, traffic simply takes another path, so there is no single point of failure; the price is a large number of links, \(n(n-1)/2\) for \(n\) nodes.

A bus fails if its single backbone cable is cut, a star fails if its central hub fails, and a simple ring is broken by the failure of any one node or link. Each of these has a single point of failure, which is why mesh is the most reliable.

Answer: C

The correct matching is a-iv, b-iii, c-i, d-ii.

• An algorithm is a set of explicit and finite steps for solving a problem.
• A flowchart represents those steps pictorially, as boxes joined by direction lines.
• Program code is the set of instructions written for the computer.
• A program test is followed by debugging, finding and removing the errors the test reveals.

The other options misplace at least one pair, for example giving debugging to the algorithm or to program code. Only one option matches all four.

Answer: B

The correct matching is a-iii, b-iv, c-ii, d-i.

• A boot virus infects the boot sector of floppy disks or the master boot record (printed 'master book record').
• A macro virus spreads through application software, in macros of documents and spreadsheets.
• A file virus is matched with the general term malware.
• A polymorphic virus encrypts and changes itself with each infection to avoid detection by scanners.

Boot virus with (iii) and polymorphic virus with (i) are the clear pairs. Only one option has both, since the near miss swaps (i) and (ii) for the file and polymorphic viruses.

Answer: C

The key's order is (ii) (iv) (iii) (i): Yahoo, Google, Ask, Bing.

Yahoo was founded in 1994 and Google in 1998. The key dates Ask from 2006, when Ask Jeeves (launched in 1996) dropped the butler and relaunched under the name Ask.com. Microsoft's Bing came last, in 2009, replacing Live Search.

Taken as Ask Jeeves, Ask would come before Google, but no option gives that order, so the key's reading is the only one an option matches. Every other option starts with a newer engine than Yahoo, which was the first of the four.

Answer: D

The basic web services platform is XML and HTTP, so the answer is (ii) and (iii) are correct.

Web services let applications exchange data over the web regardless of platform. Their basic platform combines XML, which carries the data in a self-describing, platform-neutral form, with HTTP, the transport protocol that already runs everywhere on the web. Standards such as SOAP and WSDL are built on these two.

RDF is a data model for describing resources on the semantic web, and Java is one programming language among many in which web services may be written. Neither is part of the basic platform, so every option naming (i) or (iv) is wrong.

Answer: B

The technology that uses radio-frequency electromagnetic waves is Wi-Fi.

Wi-Fi, the wireless LAN family of IEEE 802.11 standards, transmits data by radio waves, mainly in the 2.4 GHz and 5 GHz bands. That is what lets laptops and phones connect to a network without cables.

The other options use different media. Li-Fi transmits data with visible light from LED lamps, not radio waves. Optical cables carry pulses of light through glass fibre, and co-axial cables carry electrical signals along a copper conductor. Only Wi-Fi uses radio frequencies through the air.