INFORMATİON TECHNOLOGİES

100 Gigabit Ethernet standard was ratified in 2010. D is the correct answer.

Computer networks allow the users to:

• Exchange and share data and files

• Communicate with each other via e-mails, video calls, instant messaging, etc.

• Share a hardware resource such as a printer or a scanner

• Share Internet connections

• Store and access data centrally 

D is the correct answer.

A network interface controller (NIC) is a circuit board that enables a computer to connect to a network. A is the correct answer.

A hub is a multiport repeater that is used to connect segments of a local area network. A is the correct answer.

A firewall is a protective system that lies between a computer network and the Internet. C is the correct answer.

The Web is based on four key technologies:HTML (Hypertext Markup Language),HTTP (Hypertext Transfer Protocol), Web Servers and Web Browsers. E is the correct answer.

Twisted-pair cable is the most commonly used transmission media due to easy installation and low prices. C is the correct answer.

The disadvantages of optical fibers are expensiveness and difficulty of installation and maintenance. E is the correct answer.

A metropolitan area network (MAN) is a computer network that usually covers a campus or a city.D is the correct answer.

Data Link Layer is responsible for providing error-free transfer of data frames from one node to another over the physical layer. A is the correct answer.

Visual circuits are connection-oriented while the datagrams are connectionless. In visual circuits, the sub-network handles errors.However, in datagrams, errors are checked and handled by the host. It is a fact that the implementation of datagrams is easier than virtual circuits. The correct answer is E.

The classification of transmission media is as follows :

Guided Media : 

I. Twisted Pair

II. Coaxial Cable

III. Optical Fiber

Unguided Media

IV. Radio Wave

V. Microwave

The correct answer D.

A coaxial cable is a type of cable that contains two parallel conductors. Although coaxial cables have high bandwidth and they can be used over long distances, they are difficult to install and expensive than twisted pair cables. The correct answer is A.

A local area network (LAN) interconnects communication devices within a small geographical area such as an office, home, building, or factory. The main purpose of building a LAN is to provide an environment for workstations and personal computers to exchange information and share resources (e.g., network storage, printers, and applications).The correct answer is C.

In a mesh topology, each device has a pointto-point connection with a single or multiple devices. Either routing or flooding operations can transmit the messages. Since there exist redundant links in the network, the cabling cost is high in this topology. The correct answer is C.

Both the OSI and the TCP/IP has the application layer. The correct answer A.

Presentation Layer translates data to a standard format. It is responsible for character code translation, data conversion, compression, and encryption. The correct answer is D.

While the OSI is a theoretical guidance model, the TCP/IP is practically used for transmission of data over the Internet. • The OSI has seven layers while the TCP/IP has four layers. • While the transport layer in the OSI guarantees the delivery of packets, the transport layer in the TCP/ IP does not ensure delivery. • Replacing a protocol is easy in the OSI, harder in the TCP/IP. • The TCP/IP does not clearly distinguish between services, interfaces, and implementations, whereas, the OSI does. Therefore the correct answer is B.

The explosive use of the Internet has increased the potential of web browser attacks. Man-in-theBrowser attacks use Trojan horses to infect the browsers. These attacks usually try to obtain banking and credit card information.The correct answer is C.

Accounting management aims to track the usage of computation and network resources to provide a fair distribution of resources among users. The corret answer is C.