Computer Science Test - 8

The correct answer is Internet Protocol.

Key Points

• The Internet Protocol (IP) is the network layer communications protocol in the Internet protocol suite 
• For relaying datagrams across network boundaries.
• Its routing function enables internetworking, and essentially establishes the Internet.
• IP has the task of delivering packets from the source host to the destination host solely based on the IP addresses in the packet headers. 

Additional InformationInternet Service Provider;

• An Internet Service Provider (ISP) is an organization that provides services for accessing, using, or participating in the Internet.
• Internet service providers can be organized in various forms, such as commercial, community-owned, non-profit, or otherwise privately owned.

The correct answer is Network.

 Key Points

• A server is a computer program or device that provides a service to another computer connected to a network. 
• A client is a system that uses remote services from a server. 
• A computer network is a set of computers sharing resources located on or provided by network nodes.

Additional Information

• Mainframe- A mainframe is the central data repository, or hub, in a corporation's data processing centre, linked to users through less powerful devices such as workstations or terminals. The presence of a mainframe often implies a centralized form of computing, as opposed to a distributed form of computing.
• Supercomputer- A supercomputer is a computer with a high level of performance as compared to a general-purpose computer. The performance of a supercomputer is commonly measured in floating-point operations per second instead of million instructions per second.

Key Points

There is a total of 32 bits in the IPv4 address space.

For example, if a network has the address “192.0. 2.0/24”, the number “24” refers to how many bits are contained in the network. From this, the number of bits left for address space can be calculated.

Hence the correct answer is 32.

Additional Information

• IPv6 is written in hexadecimal notation, separated into 8 groups of 16 bits by the colons, thus (8 x 16 = 128) 128 bits in total.
• In a LAN, each node is assigned a physical address, also known as a MAC/Ethernet address. This address is unique to each of the nodes on the LAN and is 6 bytes (48 bits)

The correct answer is Internet Service Provider (ISP).

Key Points

• Internet service provider (ISP) 
  • It is a company that provides web access to both businesses and consumers. Hence, Option 1 is correct.
  • ISPs may also provide other services such as email services, domain registration, web hosting, and browser services.
  • An ISP has the equipment and the telecommunication line access required to have a point-of-presence on the Internet for the geographic area served.
  • The larger ISPs have their own high-speed leased lines so that they are less dependent on the telecommunication providers and can provide better service to their customers.
  • Among the largest, national and regional ISPs are AT&T WorldNet, IBM Global Network, MCI, Netcom, UUNet, and PSINet.
• Additional Information

The correct answer is 192.10.24.451.

• Any address that begins with a 0 is invalid.
  • Exception - as a default route
• Any address with a number above 255 is invalid IP.
• Any address that has more than 3 dots is invalid IP.
• Any address that begins with a number between 240 and 255 is reserved and is invalid.
• Any address that begins with a number between 224 and 239 is reserved for multicast, and it is probably invalid.

Key Points

• An Internet Protocol address (IP address) is a numerical number assigned to every computer and device.
• It is used when connected to a computer network that uses the Internet Protocol for communication.
• An IP address serves two main functions:
  • host or network interface identification
  • location addressing.

​The correct answer is Server.

• The computer that provides resources to other computers on a network is known as Server.

Key Points

• A server commonly refers to a computer program that receives and responds to requests made over a network.
• It receives the request for a web document from the client and sends the requested information to the client's computer on the Internet.
• A device can be both a client and a server at the same time, as an individual system has the ability to provide resources and use them from another system in one go. There are different types of servers: Web server, Application server, Cloud server, Database server, Print server, Proxy server, File server, Mail server, Standalone server, Domain name service.

Additional Information

Network

• A network set up by connecting two or more computers and other supporting hardware devices through communication channels is called a computer network.
• It enables computers to communicate with each other and to share commands, data, etc., including the hardware and software resources.
• The important computer networks are LAN, MAN, and WAN.
  • A Local Area Network (LAN) is a computer network that interconnects computers within a limited area such as a residence, school, laboratory, university campus, or office building.
  • Metropolitan Area Network (MAN) is a high-speed network that spreads over a large geographical area such as a metro city or town.
  • A Wide Area Network (WAN) is a telecommunications network that extends over a large geographic area for the primary purpose of computer networking.

Super Computer

• Supercomputers are the biggest and fastest computers.
• They are designed to process a huge amount of data.
• A supercomputer can process trillions of instructions in a second.
• It has thousands of interconnected processors.
• Supercomputers are particularly used in scientific and engineering applications such as weather forecasting, scientific simulations, and nuclear energy research.

Microcomputer

• A microcomputer is also known as a personal computer.
• It is a general-purpose computer that is designed for individual use.
• It has a microprocessor as a central processing unit, memory, storage area, input unit, and output unit.
• Laptops and desktop computers are examples of microcomputers.

Important Points

• The first supercomputer was developed by Roger Cray in 1976.
• Father of computer - Charles Babbage.

The correct answer is Firewall.

Key Points

• A firewall
  • It is a system designed to prevent unauthorized access to or from a private network. Hence, Option 4 is correct.
  • You can implement a firewall in either hardware or software form, or a combination of both.
  • Firewalls prevent unauthorized Internet users from accessing private networks connected to the internet, especially intranets.
  • All messages entering or leaving the intranet (the local network to which you are connected) must pass through the firewall, which examines each message and blocks those that do not meet the specified security criteria.
  • In protecting private information, a firewall is considered the first line of defense; it cannot, however, be considered the only such line.
  • Firewalls are generally designed to protect network traffic and connections, and therefore do not attempt to authenticate individual users when determining who can access a particular computer or network.
  • An inter-network connection device that restricts data communication traffic between two connected networks.
  • A firewall may be either an application installed on a general-purpose computer or a dedicated platform (appliance), which forwards or rejects/drops packets on a network.
  • Typically firewalls are used to define zone borders. Firewalls generally have rules restricting which ports are open.

The correct answer is Both I and II.

Key Points

• Each network that runs TCP/IP must have a unique network number.
• Every machine on the network must have a unique IP address.
• There are two versions of IP addresses used till now.

1. IP version 4 (IPv4) 
2. IP version 6 (IPv6)

• The IPv4 address is a 32-bit number that uniquely identifies a network interface on a machine.
• An IPv4 address is typically written in decimal digits, formatted as four octets that are separated by periods.
• Each 8-bit field represents a byte of the IPv4 address.
• This form of representing the bytes of an IPv4 address is often referred to as the dotted-decimal format.
• The bytes of the IPv4 address are further classified into two parts: the network part and the host part.
• The following figure shows the component parts of a typical IPv4 address.
• 129.144.50.56.

• Internet Protocol version 6  is the most recent version of the Internet Protocol.
• IPv6 uses a 128-bit address, allowing 2128, or approximately 3.4×1038 addresses.
• IPv6 addresses are represented as eight groups, separated by colons, of four hexadecimal digits.
• IPv6 was developed by the Internet Engineering Task Force.

Additional Information

Components of IP address

• Network Part
  • The network part specifies the unique number that is assigned to the network. 
  • The networks part also identifies the class of network that is assigned. 
• Host Part
  • This is the part of the IPv4 address that is assigned to each host. 
  • The host part uniquely identifies the machine on our network.
  •  For each host on our network, the network part of the address is the same, but the host part must be different.

The correct answer is URL.

A Uniform Resource Locator (URL), colloquially termed a web address, is a reference to a web resource that specifies its location on a computer network and a mechanism for retrieving it. It is the fundamental network identification for any resource connected to the web (like images or sound files).
A URL has the following format:

• The protocol specifies how the information from the link is transferred.
• The protocol used for web resources is HyperText Transfer Protocol (HTTP).
• The protocol is followed by a colon, two slashes, and then the domain name.
• The domain name is the computer on which the resource is located.
• Links to particular files are specified after the domain name as shown above in the format.

Hence, URL is the name for a webpage address.

The correct answer is 48.

Key Points

• A media access control address (MAC) is a unique identifier assigned to a network interface controller for use as a network address in communications within a network segment.
• This use is common in most IEEE 802 network technologies, including Ethernet, Wi-fi, and Bluetooth.

Additional Information 

• Every NIC ( Network Interface Controller) has a hardware address that's known as a MAC, for media access control where IP addresses are associated with TCP/IP (networking software), MAC addresses are linked to the hardware of network adapters.
• MAC addresses are recognizable as six groups of two hexadecimal digits, separated, by hyphens, colons, or without a separator.
• A MAC address is a 48-bit number.
• A network interface controller is a computer hardware component that connects a computer to a computer network.