23-12-2017, 04:17 PM
NETWORK DEVICES
Modem (Modulator Demodulator)
*It is a device that acts as analog to digital and digital to analog signal converter.
*It helps to transmit signals through telephone lines.
ISDN
*It is a phone line facility provided by the telecome company
ISDN Modem
*Modem is used to provide internet through ISDN
HUB
*It is a device to connect more than one computer together in a network
*Hub takes data that comes from one channel and sends out to all other channel on the hub.
*Hub is also known as - Concentrator
ISP
*Internet Service Provider eg: VSNL, Asianet, Reliance
Optical Fibre Cable
*Medium that is used to transmit data at high speed over internet - Optical Fibre Cable
Repeater
*Repeater is an electronic device that receives a signal and retransmits, it at a higher level or higher power .
Router
*A router is a device that forwards data packets along networks.
*A router is connected to atleast two net works, commonly two LANs or WANs or a LAN and its ISP’s network.
*Device which enables movement of data from one network to other network - Router
Gateway
*Gateway is a router or a proxy server that routes between networks.
Bridge
*Bridge is a device used to connect two segments of a LAN or two LAN
Bluetooth
*A short range wireless technology used to connect and exchange information between device such as PCs, Mobile phones, Laptops etc
WiFi
*WiFi - Wireless Fidelity
*It is a wireless local area network.
*It allows electronic device to exchange data wirelessly using radio waves.
*WiMAX - Worldwide Interoperability for Microwave Access
*Which of the following is NOT a requirement for operating wi-fi network?
(a) Wireless router (b) Transponders
(c ) Antenna (d) Wireless adapter
Ans : (b) Transponders
Knowledge +
*A device mounted on a communication satellite which receives, amplifies, retransmit signals from earth stations
Ans : Transponder
IP address
*IP address is a numerical value assigned to each device participating in a computer network
*IP address is unique
*Commonly it is a 32 bit number
*The system of 32 bit number IP addressing is known as - IPv4
*The system of 128 bit number IP addressing is known as - IPv6
*IPv6 address is 96 bit more than that of IPv4
*ICANN Internet Corporation for Assigned Names and Numbers (ICANN) is a private Organization started in 1998 to oversee a number of internet related tasks.
Client Server Computing
*A methodology of architecturing computer applications in which clients request services and servers provide them.
eg: Email clients retrieve email from mail servers.
*Information from server computer to client computer travels in the form of packets.
*Remote login : - The facility to login and use a remote computer in a network from a user’s terminal.
E- Mail
*E- mail is a digital message from an author to one or more recipients.
*Email was introduced by
Ans : Ray Tomlinson
*First message that sent through the e-mail
Ans : QWERTYUIOP
*Voice Mail - Voice mail system allow users to send recorded audio message to a recipient through e- mail.
*E- mail client (E- mail reader):- It is a computer program used to access and manage a user’s e-mails.
*It is also known as Mail Users Agent (MUA) Eg.Mozilla Thunderbird, Outlook Express.
*Email service provided by Google
Ans : Gmail
Hot Mail
*Email service provided by Microsoft
Ans : Hotmail
*Hotmail was invented by
Ans : Sabeer Bhatia (India), Jack Smith
*Hotmail was owned by Microsoft and renamed as outlook.com
