Computer: Communication and Network

What GPS?

( Global Position System) use satellite communications for global position

What is the function of an NOS?

( Network operating System) control and coordinate the activites of all computers and other devices on a network. these activites include electronic communication and the sharing of information and resources

What is a DSL?

(Digital Subscriber Line) Modem uses standard phones lines to create a high speed connection directly to your phone company offices. These devices are usually external and connect to the system unit using either a USB or an Ethernet port.

What is a Wireless Modem?

- A.K.A WWAN( Wireless wide area network) modem -Almost all computers today have built in wireless modems. -For those that do not wireless adapter cards are avaiable that plug into USB or special card ports

What is a Coaxial Cabel?

- High frequency transmission cable, replaces the multiple wires of telephone lines with a single solid copper core - in terms of the number of telephones connections, coaxial cable has over 80 times the transmission capacity of twisted pair. - Coaxial Cable is used to deliver television signals as well as to connect computers in a netework

What is the function of a modem?

- Short for modulator Demodulator, is the name of the process of converting from digital to analog

What is Fiber-Optic Cable?

- Transmit data as pulses of light through tiny tubes of glass -the data transmission speed of fiber optic are incredible - Compared to coaxial cable is used to deliver television signals as well as to connect computer in a network

What is Wi-Fi?

- Uses high frequency radio signals to transmit data. - A number of standard for Wi-Fi exist and each can send and recieve data at a different speed

What is Microwave Commnunication?

- Uses high frequency radio waves - IT is sometimes referred to as line of sight communication because microwaves can only travel in a straight line of sight communication because microwaves can only travel in a straight line - Because the can not bend with the curvature of the earth they can be transmitted only over relativly short distance, - Microwave is a good medium for sending data between building in a city or on a large colleage campus - for longer distances the waves must be relayed by means of microwave dishes or antennas

What is a Cable Modem?

- Uses the same coaxial canle as your televsion -Like a DSL modem, a cable modem creates high-speed connections using the system units USB or Ethernet?

What is Cellular Service Providers?

- including Verzion ,AT&T, Sprint, and T-Mobile , support voice and data transmission to wireless devices using cellular networks

What is a LAN?

- net

What is IP address ?

- the internet uses that to deliver e-mail and to locate websites using a unique numeric address

What are Protocols?

- the rules for exchanging data between computers

What is Infrared?

- unlike radio waves it uses infrared light to communicate over short distances - like microwave transmissions, infrared light is a line of sight communication - Light waves can only travel in a straight line, sending and receiving devices must be in clear view of one another without any obstructions blocking that view. -one of the most common infrared devices is the TV remote control

What is Medium Band?

- used in special leased lines to connect midrange computers and mainframes as well as to transmit data over long distance. - This bandwidth is capable of very high speed data transfer

What are Sending and Receiving Devices?

These are often a computer or specialized communication device. They originate (send) as well as accept (receive) messages in the form of data, information, and/or instructions.

What is Data Transmission Specification?

These are rules and procedures that coordinate the sending and receiving devices by precisely how the message will be sent across the communication channel.

What do Communication Channels do?

These channels actually carry the data from one computer to another. there are two categories of communication channels. one category connects sending and receiving devices by providing a physical connection such as wire or cable, the other category is wireless

What Connection Devices?

These devices act as an interface between the sending and receiving devices and the communication channel. They convert outgoing messages into packets that can travel across the communication channel. they also reverse the process for incoming messages.

What is TCP/IP?

a widley used internet protocol involve 1) Identifying Sending and Receiving Devices 2) Breaking Information into small parts or packets for transmission across the Internet

What is Voiceband?

also known as Low Bandwidth, is used for standard telephone communication. Personal computers with telephones modems and dial-ups service use this Bandwidth -While effective for transmitting text documents it is too slow for many types of transmission, including high quality audio and video

What is the standard protocol for the Internet?

https or hypertext transfer protocol secure is widely used to protect the transfer of sensitive information

What is a computer network?

is a communication system that connects two or more comptuers so that they can exchange information and share resources -Networks can be setup in different arrangement's to suit users needs

What is Computer Connectivity?

is a concepts related to using computer networks to link people and resources. for example connectivity means that you can connect your personal computer to other computer and information sources almost anywhere.

What is bandwidth?

is a measurement of the width or capacity of the communication channel

Cable Service...

is provided by cable televsion companies using their existing televison cables, these connections are usually faster than DSL

Digital Subscriber Line ...

is provided by telephone companies using existing telephone lines to provide high speed connections

What are Communication channels?

is the actual connection or transmission medium that carries the message. This medium can be a physical wire or cable or it can be wireless.

What is Computer Communications?

is the process of sharing data, programs, and information between two or more computers.

What is Broadband?

is widely used for DSL, cable and satellite connections to the internet. Several users can simultaneously use a single broadband connection for high speed data transfer

What is Baseband?

is widely used to connect individual computers that are located close to one another -Like broadband it is able to support high speed transmission -unlike broadband, however, baseband can only carry a single signal at a time.

What is Packets?

message is sent reformatted or broken down into small parts -each packet is then sent separately over the internet, possibly traveling different routes to one common destination -at the receiving end the packets are reassembled into the correct order

What is a network Administrator?

-a computer specialist responsible for efficient network operations and implementation of new networks

What is a Twisted Pair Cable?

-consists of pairs of copper wire that are twisted together. -Both standard Telephones Lines and Ethernet Cables use Twisted Pair - Ethernet cables are often used in networks and to connect a variety of components to the systems unit

What is Bluetooth?

-is a short range radio communication standard that transmit data over short distances of up to approximately 33 feet. - Bluetooth is widely used for wireless headsets, printer connections, and handheld devices

What is FiOS ?

-is showing up in some areas but it is new technology and not widely available -Current providers of FiOS include Google and Verzion with speeds faster than cable or DSL connenctions

What are the three types of modems?

1) DSL 2) Cable Modem 3)Wireless Modem

What are the five high speed connection services?

1) Digital Subscriber Line ( DSL) 2) Cable Service 3) Fiber Optic Service (FiOS) 4) Satellite Connection Services 5) Cellular Service Providers

What are the four generations of mobile connections?

1) First Genetation 1G 2) Second Generation 2G 3) Third Generation Mobile Telecommunications 3G 4) Fourth Generation Mobile Telecommunications 4G

What the Four elements of every communication System?

1) Sending and Receiving devices 2) Connection Devices 3) Data Transmission Specification 4) Communication Channel

What are the three Physical Channel?

1) Twisted Pair Cable 2) Coaxial Cable 3) Fiber Optic Cable

What are the four catergories of Bandwidth?

1) Voiceband 2) Medium Band 3) Broadband 4) Baseband

What are Nodes?

Any device that is connected to a network -it could be a computer, printer, or data storage device

What are routers?

a node that forward or routes data packers from one network to their destination in another network

What are Client?

a node that requests and uses resources available from other nodes -typically a client is a users personal computer

What are Servers?

a node that shares resources with other nodes. Dedicated servers specialize in peforming specific tasks. -Depending on the specific task, they may be called an application server, communication server, database server, file server, printer or web server

What is the wireless revolution?

a revolution that is expected to dramatically affect the way we communicate and use computer technology

What are Directory Server?

a specialized server that manages resources such as user accounts for an entire network

What are host?

any computer systems connected to a network that provides access to its resources

What are Switches?

central node that coordinates the flow of data by sending messages directly between sender and receiver nodes. a hub previously filled this purpose by sending a received message to all connected nodes rather than just the intended node.

What is the function of an NIC ?

these are expansion cards located within the system unit that connect the computer to a network -sometimes referred to as a LAN adapter