Introducing NetworksIntroducing Networks

Introduction to NetworkingIntroduction to Networking

• Network– Term that describes the connection of two or more

computers by some type of medium, including:• Wire cable

• Fiber-optic cable

• Infrared

• Radio equipment

Origin of NetworkingOrigin of Networking

• Difficult to place actual origin as many devices have been networked throughout history

• Today, networks include a wide variety of computers and peripheral components

• Systems that are part of a network do not have to be identical

Why Do We Use Networks?Why Do We Use Networks?

• Convenience

• People expect interoperability from electronic devices

• Computer networks allow for the transfer of files, data, and even shared applications without copying anything to floppy disk

Why Do We Use Networks?Why Do We Use Networks?

Why Do We Use Networks?Why Do We Use Networks?

Related TermsRelated Terms

• Media– Refers to the wire cabling that form the connections in

most networks– Some networks use wireless transmission media, such as

infrared or radio signals– Cable, glass, or telephone lines that host the signal

from one computer to another on the network• Electromagnetic interference (EMI)

– Electric noise that disrupts signals on cables• Wireless

– Communications that are not conducted over physical wires or cables

Client/Server NetworksClient/Server Networks

• Networks that have computers as servers and computers that act as clients to those servers

• Server host that resources for the clients to use and provide security

• A client is the computer that request resources from the server.

Client/Server NetworksClient/Server Networks

• Types of servers on a network:

– Print server

– File server

– Database server

– Remote access server (RAS)

– Web server

Peer-to-PeerPeer-to-Peer

• When every computer on a network acts as both a client and a server, the network is a peer-to-peer network

• In a peer-to-peer network, all computers can share resources with other computers

• Peer-to-peer networks are also known as “workgroups”

LAN, WAN, MAN, SANLAN, WAN, MAN, SAN

• A local area network (LAN) is contained within a company or department and located in a single geographic area

• A wide area network (WAN) spans multiple geographic areas and is usually connected by common telecommunication carriers

Or a network that spans two or more geographically diverse

locations

• A metropolitan area network (MAN) is an intermediate specification that defines networks confined to a fairly restricted geographic area

LAN, WAN, MAN, SANLAN, WAN, MAN, SAN

• A storage area network (SAN) is refers to a series of storage devices that are networked together to provide very fast data storage for a network or subnetwork

Or a subsystem of networked storage devices physically

separated from servers

Network Operating SystemNetwork Operating System

• Network operating system (NOS)– Allows communication, security, and distribution

of data, files, and applications over a network

• End system– The location and/or set of controls that the user

can manipulate to interact with a computer or a network

NIC, Networking Hardware, and NIC, Networking Hardware, and Networking SoftwareNetworking Software

• Network interface card (NIC)– A device that allows a computer or other device to connect

to a network through the media– Hardware device that transmits and receives electronic

signals on a network• Networking hardware - Describes all the physical components of a network, such as the NIC, cable, hub, switch, router, and any related connectors or devices - a generic term that describes all the physical components of a network

NIC, Networking Hardware, and NIC, Networking Hardware, and Networking SoftwareNetworking Software

• Networking software - The programs used to run a network