Quiz 7

1. Discuss the components required for successful communications.


- Successful communications requires a sending device that initiates a transmission instruction, a communications device that connects the sending device to a communications channel, a communications 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.

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). This division of labor between components make a client server setup more efficient than a peer-to-peer network.

- 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.

- Ethernet technology allows computers to contend for access to network

-Token Ring technology controls access to network by requiring devices to pass a special signal called token.

-TCP/IP (Transmission Control Protocol/Internet Protocol) technology transmits data by breaking it up into small pieces, or packets

-802.11 (WiFi) is family of standards for wireless LANs

-Bluetooth Short-range radio waves transmit data between Bluetooth devices

-UWB specification allows data to be transferred wirelessly via short-range radio waves

-IrDA specification allows data to be transferred wirelessly via infrared light waves

-WiMax/802.16 standard that specifies how wireless devices communicate over the air in a wide area

-RFID uses radio signals to communicate with a tag placed in an object

-WAP allow wireless mobile devices to access Internet

7. Explain the purpose of communications software.

-Programs that help users establish connection to Internet, other network, or another computer

-Programs that help users manage transmission of data, instructions, and information

-Programs that provide an interface for users to communicate with one another

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 communications devices

9. Describe commonly used communications devices.

- Dial Up Modems A dial-up modem converts digital signals to analog signals and vice versa

-ISDN/DSL Modems Usually external devices in which one end connects to a telephone line and the other end connects to a port on the system unit

-Cable Modem Sends and receives data over cable television network.Broadband modem.

-Wireless Modem Allows access to the Web wirelessly from a notebook computer, a PDA, a smart phone, or other mobile device.

-Network Card Ø

Adapter card, PC Card, ExpressCard module, USB network adapter, or flash card that enables computer or device to access network .
-Wireless Access Point
Central communications device that allows computers and devices to transfer data wirelessly among themselves or wirelessly to a wired network .

-Router Connects computers and transmits data to correct destination on network.
-Hub or Switch Device that provides central point for cables in network.