Quiz no. 7

1.Discuss the components required for successful commmunications.


      Computer communications describes a process in which two or more computers or devices transfer data, instructions, and information. Successful communications requires a sending device that initiates a transmission instruction, a communications device that connects the sending device to a communications channel, acommunications channel on which the data travels, a communications device that connects the communications channel to a receiving device, and a receiving device that accepts the transmission of data, instructions, or information.

2.Identify various sending and receiving devices.

     A sending device initiates the transmission of data, instructions, and information while a receiving device accepts the items transmitted.
 
       All types of computers and mobile devices serve as sending and receiving devices in a communications system. This includes mainframe computers, servers, desktop computers, notebook computers, Tablet PCs, smart phones, portable media players, and GPS receivers.

3.Describe uses of computer communication

Communications technologies include the Internet, Web, e-mail, instant messaging, chat rooms, newsgroups, blogs, wikis, RSS, VoIP, FTP, Web folders, video conferencing, and fax machine or computer fax/modem. Users can send and receive wireless messages to and from smart phones, cell phones, handheld game consoles, and other personal mobile devices using text messaging, wireless instant messaging, picture messaging and video messaging. A wireless Internet access point lets people connect wirelessly to the Internet through a wireless Internet access point. A hot spot is a wireless network that provides Internet connections to mobile computers and devices. A cybercafé is a coffeehouse, restaurant, or other location that provides computers with Internet access. A global positioning system (GPS) analyzes signals sent by satellites to determine an earth-based receiver’s geographic location. Many software products provide a means to collaborate, or work online with other users connected to a server. A document management system provides for storage and management of a company’s documents, such as word processing documents, presentations, and spreadsheets. Groupware is software that helps people work on projects or share information over a network. Voice mail allows someone to leave a voice message for one or more people. Web services describe standardized software that enables programmers to create applications that communicate with other remote computers.

4.List of advantages of using a network.

A user can logon to a computer anywhere on the network and access their work files from the file server.

Computers can be managed centrally - with the same software installed on each one.

Time - it is much faster to install an application once on a network - and copy it across the network to every workstation.

Sharing printers, plotters, modems etc saves money and time.

Security - the Network Manager can allocate usernames and passwords to all users to try to prevent unauthorised access.

It is easy and convenient to monitor users - for example websites visited or documents printed - this can be done using software running on the server.

5. Differentiate among client/server,peer to peer, and P2P networks.

Client/server-describes the relationship between two computer programs in which one program, the client, makes a service request from another program, the server, which fulfills the request.

Peer-to-peer (P2P)-computing or networking is a distributed application architecture that partitions tasks or workloads between peers. Peers are equally privileged, equipotent participants in the application. They are said to form a peer-to-peer network of nodes.

 

6.Describe the various network communications standards.

 

7.Explain the purpose of communications software.

 

Communication software is used to provide remote access to systems and is also used to exchange messages in text, audio and video format for the purpose of communication. This software sends and receives data over telephone lines through modems. The communication software allows computers in different geographical regions to communicate with each other through terminal emulators, file transfer programs, chat and instant messaging programs.

 

8.Describe various types of lines for communications over the telephone network.

 

9.Describe commonly used communications devices.

 

Radios are communication systems that send and/or receive electromagnetic waves and consist of a transmitter, receiver, and antenna. Pagers are electronic communications devices that are used to notify or alert a user. Communication received by pagers may be numeric or alphanumeric, depending on the model and complexity of the device.

Other types of communication devices include navigation systems, such as global positioning systems (GPS) instruments and radar systems. GPS communication devices receive satellite communications and use it to provide position information. Radar communication devices use synchronized transmitters and receivers to send radio waves and detect their reflections from objects, surfaces and sub-surface structures.