Understanding Network Concepts Living Online Lesson 1 IC 3 Basics Ambrose, Bergerud, Busche, et. Al.

Introducing Networks Network—Group of two or more computers linked together  Local Area Network (LAN) Used in limited geographical area  Wide Area Network (WAN) Used in larger geographical area Made up of several connected LANs

Introducing Networks Data Communications—Transmitting data from one location to another using:  Sending device (generally a computer)  Communications device that converts computer signals (modem)  Communications channel or path (telephone lines or cable)  Receiving device (generally a computer)  Communications software

Introducing Networks Network Benefits  Increased communications  Information sharing  Hardware sharing  Software sharing  Collaborative environment, workgroups  Cost savings

Communications Media Communications Channel—Link that transfers data from one computer to another  Telephone system now transmits data including: Fax transmissions Live video  Dial-up lines provide “temporary” connection  Dedicated lines provide “permanent” connection  Switch establishes link between sender and receiver

Network Hardware Communications Hardware—Facilitates the sending and receiving of data using:  Modem Converts analog signals to digital and vice versa Enables computer to send data over telephone lines Both senders and receivers must have a modem  Cable Modem Same type as cable television Greater bandwidth, sends more data at a time

Network Hardware Network Transmission Hardware  Network interface card (NIC)--Enables sending and receiving data between the computers in a LAN  Hub--Receives and forwards data  Bridge –Computer that connects one LAN to another  Router—Directs network traffic; connects multiple networks

Types of Networks Local Area Network (LAN)  Client/server Server manages network resources May be more than one server such as printer server or database server Stores network operating system software and network versions of software applications Clients are all other computers on the network sharing server resources

Types of Networks Local Area Network (LAN)--Continued  Peer-to-peer All computers are equal Easier to set up and manage Wide Area Network (WAN)  Intranet Used within an organization  Extranet Used within an organization

Risks of Networked Computing Equipment Malfunctions System Failures Loss of Privacy and Security Computer Hackers Virus Attacks