Transcript Chap5 Part2
CHAPTER 5
Part 2
Introduction
to
Networking
Chapter Overview
Networking requirements
Network types and topologies
Network cabling
Local area network (LAN) communication.
Communication
The process of sharing data, programs, and
information between two or more computers
Communication Systems
Modem
Computer
Telephone-lines
E-mail
Networks
A computer network is a communication
system
Connects two or more computers
Allows information exchange
Network Terms
Node
Any device that is connected to a network
(Computer or printer)
Client:
Server
microcomputer
A node that shares resources with other nodes
Hub
The center or central node for other nodes
Network interface cards
(NIC)
Network operating system
(NOS)
Host computer
Minicomputer or mainframe computer
Network manager
Computer specialist or network
administrator
Basic Requirements of a Network
A network links computers for communicating
and sharing information and resources.
A network must provide
Connections ( medium and NIC)
Communications ( rules concerning how
computers talk and understand each other)
Services ( share printers, files and folders)
Types of Networks
Local area networks
Home networks
1 mile
Including a common internet connection
Metropolitan area networks (MAN)
100 miles connect buildings in a city
Wide area networks(WAN)
Local Area Networks
Cover a limited distance
Allow sharing of data, peripherals, software, and storage .
A LAN covers a relatively small area such as a classroom, school,
or a single building.
Metropolitan area network (MAN):
A MAN spans the distance of a typical metropolitan city.
The cost of installation and operation is higher.
MANs use high-speed connections such as fiber optics to achieve
higher speeds.
Fiber-optic cable
Transmit data as pulses of light through tiny tubes of
glass.
26000 times the transmission capacity of twisted pair
cable
Wide Area Networks
Span relatively large areas
Typically consist of two or more LANs
Are connected using telephone .
The Internet is a good example of a WAN.
Types of Networks
Classification by Component Roles
Peer-to-peer:
In a peer-to-peer network, all computers are considered equal.
Each computer controls its own information and is capable of functioning as
either a client or a server depending upon the requirement.
Peer-to-peer networks are inexpensive and easy to install.
They are popular as home networks and for use in small companies.
Server-based:
A server-based network offers centralized control and is
designed for secure operations.
When a client requests a resource such as a document , the
server sends the whole resource over the network to the
client , where it is processed and later returned to the server.
Network Architecture
Architecture: describes how a network is arranged
Arrangement is called topology
Types of network topology
Star
Bus
Ring
Hierarchical
Star Topology
Smaller computers linked
to a central unit
Central unit is called the
network hub
Bus Topology
Each device handles its own communication control
There is no host computer
Has a common connecting cable called a backbone
Ring Topology
Each device is connected
to two other devices
No central file server or
computer
Network Operating System
Network operating systems (NOSs) provide the ability
to share file, print, and other services.
Computers can be servers, clients, or both.
The two types of NOSs are add-ons ( Netware) and
built-in ( windows 2000).
Network Interface Cards (NICs)
Provide the physical connection between the computer’s
expansion bus and the network cable
Boost the digital signal from the computer( send signal across
the cable.
Change the data stream from wide stream to narrow stream
(parallel to serial conversion)
Move data to and from random access memory (RAM) and
manage the flow of data to and from the network cable
Buffer the data from the computer.
Installation of the NIC
Network Cabling
Specifying the Right Cable
Network Protocols
A protocol is a set of rules that manage network
communication.
A protocol suite is a group of protocols that can be
used together.
The standard protocols are
Internetwork Packet Exchange/Sequenced Packet Exchange
(IPX/SPX)
Networked Basic Input/Output System/NetBIOS Enhanced
User Interface (NetBEUI)
Transmission Control Protocol/Internet Protocol (TCP/IP)
AppleTalk
Data Link Control (DLC)
Extending a LAN
Repeaters ( an amplifier to increase the signal to
Bridges( isolate network problems and traffic, isolate the
allow transmissions over longer distance)
segment) .
Segment is a group of computers on the same network)
A bridge connects dissimilar networks together
Routers:
Gateways :
connect networks using different protocols
A router is used to send specific portions of messages directly to
the intended destination in a separate network.
or fax functions
provide access to special services such as email
Network Certification
Microsoft Certified Product Specialist (MCPS)
Microsoft Certified Systems Engineer (MCSE)
Certified Novell Administrator (CNA)
Certified Novell Engineer (CNE)
Chapter Summary
A network provides connections, communications,
and services.
Networks are either peer-to-peer or server-based.
Network topology types are star, bus, and ring.
A NIC connects the computer to the network.
Network cable types are twisted-pair, coaxial, and
fiberoptic.
A network protocol provides the rules for network
communications.
Networks can be extended with repeaters, bridges,
routers, and gateways.