14-09-2012, 11:27 AM
Data Communications and Computer Networks
networking.ppt (Size: 1.05 MB / Downloads: 71)
Network
A computer network is device, or group of devices, that allows one computer to transmit data to another computer, or group of computers.
Examples: Internet, E-Mail, Direct Connection.
Data communications - the transfer of digital or analog data using digital or analog signals.
Local Area Network
Smaller networks that are confined to a localised area.
(e.g. an office, building or factory ) are known as LANs.
Metropolitan Area Network
Network spread across a city. E.g Cable T.V.
Wide Area Network
Network spread across countries. e,.g. Internet
Network Components
The basic network components today are:
Cables
Network Adapter Cards
Hubs
Switch
Network Adapter Card
A network computer is connected to the network cabling with a network interface card, (also called a "NIC", "nick", or network adapter). Some NICs are installed inside of a computer: the PC is opened up and a network card is plugged directly into one of the computer's internal expansion slots. 286, 386, and many 486 computers have 16-bit slots, so a 16-bit NIC is needed. Faster computers, like high-speed 486s, Pentiums, PentiumII and PentiumIII, all have 32-bit, or PCI slots.
MODEM
It is a computer peripheral that allows you to connect and communicate with other computer via telephone line.
Modem changes the digital data from your computer into analog data, a format that can be carried over telephone lines.
In the same the modem receiving the call then changes the analog signal back into digital data that the computer can understand.
SWITCH
The Switching hub, sometimes called a "Switch" is a more advanced unit over the basic hub. In a basic hub, all the computers connect to it and the speed of the network is defined by the slowest computer network card connected.
Wireless Communication
Wireless communication uses radio frequencies (RF) or infrared (IR) waves to transmit data between devices on a LAN. For wireless LANs, a key component is the wireless hub, or access point, used for signal distribution. To receive the signals from the access point, a PC or laptop must install a wireless adapter card (wireless NIC). Some common applications of wireless data communication include the following:
Accessing the Internet using a cellular phone
Establishing a home or business Internet connection over satellite
Beaming data between two hand-held computing devices
Using a wireless keyboard and mouse for the PC
Another common application of wireless data communication is the wireless LAN (WLAN), which is built in accordance with Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards. WLANs typically use radio waves (for example, 902 megahertz [MHz]), microwaves (for example, 2.4 GHz), and IR waves (for example, 820 nanometers [nm]) for communication. Wireless technologies are a crucial part of the today's networking.
networking.ppt (Size: 1.05 MB / Downloads: 71)
Network
A computer network is device, or group of devices, that allows one computer to transmit data to another computer, or group of computers.
Examples: Internet, E-Mail, Direct Connection.
Data communications - the transfer of digital or analog data using digital or analog signals.
Local Area Network
Smaller networks that are confined to a localised area.
(e.g. an office, building or factory ) are known as LANs.
Metropolitan Area Network
Network spread across a city. E.g Cable T.V.
Wide Area Network
Network spread across countries. e,.g. Internet
Network Components
The basic network components today are:
Cables
Network Adapter Cards
Hubs
Switch
Network Adapter Card
A network computer is connected to the network cabling with a network interface card, (also called a "NIC", "nick", or network adapter). Some NICs are installed inside of a computer: the PC is opened up and a network card is plugged directly into one of the computer's internal expansion slots. 286, 386, and many 486 computers have 16-bit slots, so a 16-bit NIC is needed. Faster computers, like high-speed 486s, Pentiums, PentiumII and PentiumIII, all have 32-bit, or PCI slots.
MODEM
It is a computer peripheral that allows you to connect and communicate with other computer via telephone line.
Modem changes the digital data from your computer into analog data, a format that can be carried over telephone lines.
In the same the modem receiving the call then changes the analog signal back into digital data that the computer can understand.
SWITCH
The Switching hub, sometimes called a "Switch" is a more advanced unit over the basic hub. In a basic hub, all the computers connect to it and the speed of the network is defined by the slowest computer network card connected.
Wireless Communication
Wireless communication uses radio frequencies (RF) or infrared (IR) waves to transmit data between devices on a LAN. For wireless LANs, a key component is the wireless hub, or access point, used for signal distribution. To receive the signals from the access point, a PC or laptop must install a wireless adapter card (wireless NIC). Some common applications of wireless data communication include the following:
Accessing the Internet using a cellular phone
Establishing a home or business Internet connection over satellite
Beaming data between two hand-held computing devices
Using a wireless keyboard and mouse for the PC
Another common application of wireless data communication is the wireless LAN (WLAN), which is built in accordance with Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards. WLANs typically use radio waves (for example, 902 megahertz [MHz]), microwaves (for example, 2.4 GHz), and IR waves (for example, 820 nanometers [nm]) for communication. Wireless technologies are a crucial part of the today's networking.