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1. Discuss the components required for successful communications.

      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 communications.

     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.

4. List advantages of using a network.

>Speed                                   >Cost                          >Security

>Centralized Software Management                               >Resource Sharing

>E-mail                                  >Work group computing 

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

       A client/server setup has servers, which are dedicated machines that perform specific functions in the network. A server can be used to manage a network's email (mail server), database (database server), files (file server), printers (print server), or access an anti-virus (security server). 

      A peer-to-peer network setup Simple network that connects fewer than 10 computers. Each computer, or peer, has equal capabilities. 

      P2P is an Internet peer-to-peer network Enables users to connect to each other’s hard disks and exchange files directly.

6. Describe the various network communications standards.

- Network standards defines:

•  Way devices access the medium
•  Speed on different types of networks
•  Types of network technology (cable / wireless)

- Protocols

•  Rules on how devices communicate with each other
•  Data format used
•  Coding Scheme
•  Error Handling
•  Sequencing techniques etc.
•  Hardware / Software Vendors try to meet these guidelines

- ANSI, IEEE

- Standardizing Organization

7. Explain the purpose of communications 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.

• PSTN - Worldwide telephone system that handles voice-oriented telephone calls.
• Dial-up line - Temporary connection using telephone line for communications.
• Dedicated line - Always on connection between two communication devices.  
• Five types of digital dedicated lines are ISDN line, DSL, FTTP, T-carrier line and ATM.

9. Describe commonly used communications devices.

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Dial-up modem

• A dial-up modem converts digital signals to analog signals and vice versa
• Usually in the form of an adapter card

- DSL Modem / ISDN Modem-Cable Modem

- Router

• Connects computers and transmits data to correct destination on network. 
• 
  

- Cable Modem

•  Sends and receives data over cable television (CATV) network
•  Much faster than dial-up modem or ISDN
•  Sometimes called a broadband modem

- Wireless Modem 

• Allows access to the Web wirelessly from a notebook computer, a smart phone, or other mobile device. 

- Hub or Switch 

Send and receive digital data from DSL(Digital Subscriber Line) / ISDN