chapter one an introduction to networking welcome to networking and telecommunications professor:...

Chapter OneChapter OneAn Introduction to NetworkingAn Introduction to Networking

Welcome to Networking and Telecommunications

Professor:

Ken Clifton, CISSP, MCSE, MCSD, MCDBA, Network+, A+, CTT+, CXE

Networks and Standalone Networks and Standalone ComputersComputers

NetworkNetwork Group of computers and other devices Group of computers and other devices

connected by some type of transmission mediaconnected by some type of transmission media Networks enable users to share devices and Networks enable users to share devices and

data, collectively called a network’s data, collectively called a network’s resourcesresources

Standalone computerStandalone computer Uses programs and data only from its local Uses programs and data only from its local

disks and is not connected to a networkdisks and is not connected to a network

SneakernetSneakernet

Method of sharing data by copying it to a disk Method of sharing data by copying it to a disk and carrying the disk from computer to computerand carrying the disk from computer to computer

Figure 1-1: Data sharing before the advent of networks

Local and Remote ComputersLocal and Remote Computers

Local computerLocal computer Computer on which user is workingComputer on which user is working

Remote computerRemote computer Computer that user controls or works on via Computer that user controls or works on via

network connectionnetwork connection

Peer-to-Peer NetworkPeer-to-Peer Network

Computers communicate on single segment of cable and Computers communicate on single segment of cable and share each other’s data and devicesshare each other’s data and devicesSimple example of a local area network (LAN)Simple example of a local area network (LAN)

Figure 1-2: Simple peer-to-peer network

Local Area Network (LAN)Local Area Network (LAN)

Network of computers and other devices Network of computers and other devices confined to relatively small spaceconfined to relatively small space

LANs involving many computers are LANs involving many computers are usually server-basedusually server-based On a On a server-based networkserver-based network, special , special

computers (known as computers (known as serversservers) process data ) process data for and facilitate communication between for and facilitate communication between other computers on the network (known as other computers on the network (known as clientsclients))

Networking BasicsNetworking Basics

WorkstationWorkstation Computer that typically runs a desktop Computer that typically runs a desktop

operating system and connects to a operating system and connects to a networknetwork

Client/server architectureClient/server architecture Networking model in which clients use Networking model in which clients use

central server to share applications, central server to share applications, devices, and datadevices, and data

The most common network architectureThe most common network architecture


Client/server networkClient/server network Network based on client/server architectureNetwork based on client/server architecture

Network operating systemNetwork operating system Special software designed to manage data Special software designed to manage data

and other resources on a server for a number and other resources on a server for a number of clients.of clients.

Be prepared to identify examples of NOS(s)Be prepared to identify examples of NOS(s)


Figure 1-3: LAN with a file

server


Figure 1-4: An example of a complex

network

Advantages of Server-Based Advantages of Server-Based over Peer-to-Peer Networksover Peer-to-Peer Networks

User login accounts and passwords can be User login accounts and passwords can be assigned in one placeassigned in one place

Access to multiple shared resources can be Access to multiple shared resources can be centrally grantedcentrally granted

Servers are optimized to handle heavy Servers are optimized to handle heavy processing loads and dedicated to handling processing loads and dedicated to handling requests from clientsrequests from clients

Servers can connect more than a handful of Servers can connect more than a handful of computerscomputers

MANs and WANsMANs and WANs

Metropolitan area network (MAN)Metropolitan area network (MAN) Network connecting clients and servers in Network connecting clients and servers in

multiple buildings within limited geographic multiple buildings within limited geographic areaarea

Wide area network (WAN)Wide area network (WAN) Network that spans large distance and Network that spans large distance and

connects two or more LANsconnects two or more LANs The The InternetInternet is an example of a very intricate is an example of a very intricate

and extensive WAN that spans the globeand extensive WAN that spans the globe

WANWAN

Figure 1-5: A simple

WAN

Elements Common to AllElements Common to AllServer-Based NetworksServer-Based Networks

ClientClient In addition to referring to a computer on the In addition to referring to a computer on the

network, may also refers to human network, may also refers to human useruser of of client workstationclient workstation

Server – what differentiates a server?Server – what differentiates a server?WorkstationWorkstationNetwork interface card (NIC)Network interface card (NIC) Enables workstation to connect to the network Enables workstation to connect to the network

and communicate with other computersand communicate with other computers


Figure 1-6: A network interface

card (NIC)

Network operating system (NOS)Network operating system (NOS) Be able to identify examples of NOS.Be able to identify examples of NOS.

HostHost Server that manages shared resourcesServer that manages shared resources

NodeNode Client, server, or other device that can Client, server, or other device that can

communicate over a network and that is communicate over a network and that is identified by a unique identifying number, identified by a unique identifying number, known as its network addressknown as its network address



TopologyTopology Physical Physical

layout of layout of computer computer networknetwork

Figure 1-7: Commonly used network topologies


ProtocolProtocol Rules network uses to transfer dataRules network uses to transfer data

Data PacketsData Packets The distinct units of data transmitted from one The distinct units of data transmitted from one

computer to another on a networkcomputer to another on a network


AddressingAddressing Scheme for assigning unique identifying Scheme for assigning unique identifying

number to every workstation on networknumber to every workstation on network The number that uniquely identifies each The number that uniquely identifies each

workstation and device on a network is its workstation and device on a network is its addressaddress


Transmission Transmission mediamedia Means Means

through through which data which data are are transmitted transmitted and receivedand received

Figure 1-8: Examples of network transmission media

How Networks Are UsedHow Networks Are Used

ServicesServices Features provided by a networkFeatures provided by a network

File and print servicesFile and print services

Application services (not in text)Application services (not in text)

Communications servicesCommunications services

Mail servicesMail services

Internet servicesInternet services

Management servicesManagement services

Network ServicesNetwork Services

File servicesFile services Refers to capability of a server to share data Refers to capability of a server to share data

files, applications, and disk storage spacefiles, applications, and disk storage space Server that provides file services is called a Server that provides file services is called a

file serverfile server

Print servicesPrint services Allows printers to be shared by several users Allows printers to be shared by several users

on a networkon a network


Application servicesApplication services Database servers, voice mail, terminal services, etc.Database servers, voice mail, terminal services, etc. Actually running a program.Actually running a program.

Communications servicesCommunications services Allow remote users to connect to a networkAllow remote users to connect to a network

Remote userRemote user Person working on a computer in a different geographical Person working on a computer in a different geographical

location from the LAN’s serverlocation from the LAN’s server Communications serverCommunications server

Server that runs communications servicesServer that runs communications services

Also referred to as Also referred to as access serversaccess servers and and remote access remote access serversservers


Mail servicesMail services Coordinate storage and transfer of e-mail between Coordinate storage and transfer of e-mail between

users on a networkusers on a network

Gateway servicesGateway services Combination of software and hardware enabling two Combination of software and hardware enabling two

different kinds of networks to exchange datadifferent kinds of networks to exchange data

Internet servicesInternet services Enable networks to communicate with the InternetEnable networks to communicate with the Internet


Management servicesManagement services Centrally administer and simplify complicated Centrally administer and simplify complicated

management tasks on the networkmanagement tasks on the network Numerous services fall under category of Numerous services fall under category of

network managementnetwork management

Important Management Important Management ServicesServices

Traffic monitoring and controlTraffic monitoring and control TrafficTraffic

Data transmission and processing activity taking Data transmission and processing activity taking place on a computer network at any given timeplace on a computer network at any given time

SegmentSegmentPart of LAN that is logically separated from other Part of LAN that is logically separated from other parts of LAN and that shares fixed amount of parts of LAN and that shares fixed amount of traffic capacitytraffic capacity


Load balancing (aka. Clustering)Load balancing (aka. Clustering) Distributing process activity evenly across a Distributing process activity evenly across a

network so that no single device is network so that no single device is overwhelmedoverwhelmed

Hardware diagnosis and failure alertHardware diagnosis and failure alert Determining when a network component Determining when a network component

fails and automatically notifying network fails and automatically notifying network administrators through e-mail or pageradministrators through e-mail or pager


Asset managementAsset management Collecting and storing data on number and Collecting and storing data on number and

types of software and hardware assets in an types of software and hardware assets in an organization’s networkorganization’s network

License trackingLicense tracking Determining how many copies of a single Determining how many copies of a single

application are currently in use on a networkapplication are currently in use on a network


Security auditingSecurity auditing Evaluating what security measures are Evaluating what security measures are

currently in force and notifying network currently in force and notifying network administrator if a security breach occursadministrator if a security breach occurs

Software distributionSoftware distribution Automatically transferring data file or program Automatically transferring data file or program

from the server to a client on the networkfrom the server to a client on the network


Address managementAddress management Centrally administering a finite number of Centrally administering a finite number of

network addresses for an entire LANnetwork addresses for an entire LAN

Backup and restoration of dataBackup and restoration of data Backing upBacking up

Copying critical files to a secure storage areaCopying critical files to a secure storage area RestoringRestoring

Retrieving data if original files are lost or deletedRetrieving data if original files are lost or deleted

Mastering the Technical Mastering the Technical ChallengesChallenges

Specialty areas in high demand for Specialty areas in high demand for networking professionals:networking professionals: Network securityNetwork security Internet and intranet designInternet and intranet design Network managementNetwork management Voice/data integrationVoice/data integration

* Consider what is easiest to outsource in this * Consider what is easiest to outsource in this environment (programming or networking)?environment (programming or networking)?

Mastering the Technical Mastering the Technical ChallengesChallenges

Specialty areas in high demand for Specialty areas in high demand for networking professionals (cont.):networking professionals (cont.): Data integrity and fault toleranceData integrity and fault tolerance In-depth knowledge of Microsoft networking In-depth knowledge of Microsoft networking

productsproducts In-depth knowledge of NetWare networking In-depth knowledge of NetWare networking

productsproducts In-depth knowledge of router configuration In-depth knowledge of router configuration

and managementand management

Pursuing CertificationPursuing Certification

CertificationCertification Process of mastering material pertaining to a Process of mastering material pertaining to a

particular hardware system, operating system, particular hardware system, operating system, programming language, or other software programming language, or other software program, then proving your mastery by passing program, then proving your mastery by passing a series of examsa series of exams

Computer Technology Association Computer Technology Association (CompTIA)(CompTIA) An association that sets industry-wide An association that sets industry-wide

standards for computer professionalsstandards for computer professionals


A+ A+ Certification established by CompTIACertification established by CompTIA Verifies knowledge about PC operation, repair, Verifies knowledge about PC operation, repair,

and managementand management

Microsoft Certified Systems Engineer Microsoft Certified Systems Engineer (MCSE)(MCSE) Certification established by MicrosoftCertification established by Microsoft Demonstrates in-depth knowledge about Demonstrates in-depth knowledge about

Microsoft’s productsMicrosoft’s products Current Counts: Current Counts:

http://www.microsoft.com/learning/mcp/certified.asphttp://www.microsoft.com/learning/mcp/certified.asp


Certified NetWare Engineer (CNE)Certified NetWare Engineer (CNE) Certification established by NovellCertification established by Novell Demonstrates in-depth understanding of Novell’s Demonstrates in-depth understanding of Novell’s

networking softwarenetworking software

Network+ (Net+)Network+ (Net+) Certification established by CompTIACertification established by CompTIA Verifies broad, vendor-independent networking Verifies broad, vendor-independent networking

technology skillstechnology skills

CCNA and CCIE Cisco CertificationCCNA and CCIE Cisco CertificationCISSP – ISC2 International Information Systems CISSP – ISC2 International Information Systems Security ConsortiumSecurity Consortium


Benefits of becoming certified include:Benefits of becoming certified include: Better salaryBetter salary Greater opportunitiesGreater opportunities Professional respectProfessional respect Access to better supportAccess to better support

Chapter SummaryChapter Summary

A Network is a group of computers or other A Network is a group of computers or other devices connected by some type of devices connected by some type of transmission mediatransmission mediaNetworks may be small or large, connecting Networks may be small or large, connecting computers in one office or across the worldcomputers in one office or across the worldAll networks offer advantages relative to the All networks offer advantages relative to the use of standalone computersuse of standalone computersSimplest form of a network still used today Simplest form of a network still used today connects a handful of computers through one connects a handful of computers through one cable and uses peer-to-peer communicationcable and uses peer-to-peer communication


A LAN is a network of computers and other A LAN is a network of computers and other devices confined to a relatively small spacedevices confined to a relatively small spaceA WAN is a network connecting two or more A WAN is a network connecting two or more geographically distinct LANsgeographically distinct LANsAll server-based networks share some common All server-based networks share some common elementselementsThe physical layout of a computer network is The physical layout of a computer network is called a topologycalled a topologyNetwork protocols are rules the network uses to Network protocols are rules the network uses to transfer datatransfer data


File and print services provide foundation for File and print services provide foundation for networkingnetworking

Communications services allow remote users to Communications services allow remote users to connect to the networkconnect to the network

Mail services allow networks users to exchange Mail services allow networks users to exchange and store e-mailand store e-mail

Internet services enable organizations to connect Internet services enable organizations to connect to the Internetto the Internet

Network management services centrally Network management services centrally administer and simplify complicated management administer and simplify complicated management tasks on networktasks on network

chapter one an introduction to networking welcome to networking and telecommunications professor:...

Documents

network connectionpeer

local area network lanfigure

data sharing

central server

simple peer

servers process data

allserverbased networksfigure

peer networkcomputers