Transcript Chapter One

Lecture One
An Introduction
To Networking
Chapter One Objectives
 Examine the objectives of networked
computing relative to standalone computing
 Identify the elements of a network
 Describe specific uses of a network
 Identify some of the certifications available
to networking professionals
 Identify the kinds of non-technical, or soft
skills to help in succeeding as a networking
professional
Networks and Standalone
Computers
 Network
– A group of computers and other devices connected
by some type of transmission media
– Networks enable users to share devices and data,
collectively called a network’s resources
 Standalone Computer
– Uses programs and data only from its local
disks and is not connected to a network.
Sneakernet
 Method of sharing data by copying it to a disk
and carrying it from computer to computer
FIGURE 1-1 Data sharing before the advent of networks
Local and Remote Computers
 Local Computer
– Computer on which a user is working
 Remote Computer
– Computer which a user controls or works on
via a network connection
Local Area Network (LAN)
 Network of computers and other devices
confined to a relatively small space, e.g.,
campus of a university, a corporate site, or
even one or a few rooms in a building.
– Peer-to-Peer Communication
– Server-Based Network
Peer-to-Peer Communication
(for simple small networks with limited number of
computers)
 Means of networking computers using a single cable
FIGURE 1-2 Simple peer-to-peer network
Server-Based Network
(Coach House networks are server-based; in fact we have
several servers)
 Network using special computers, known as
file servers, to process data for and facilitate
communication between other computers on
the network
– File Server
• Manages shared resources
– Client
• Requests or services another computer on the
network
Server-Based Network
 Workstation
– Desktop computer, which may or may not be connected
to a network (most clients are workstation computers.
Today, the line between workstations and a PCs has
been blurred.)
 Network Operating System (NOS)
– Special system software designed to manage data and
other resources on a server for a number of clients
– Coach House: servers run under Microsoft Window
NT and Sun Microsystems' Solaris NOS's.
Client/Server Architecture
 Networking
model in which
clients use a
central file
server to share
applications
such as
compilers,
utility and
other software.
FIGURE 1-3 LAN with a file server
Client/Server Architecture
FIGURE 1-4 An example of a complex network
Advantages of Server-Based over
Peer-to-Peer Networks
 User login accounts and passwords can be
assigned in one place
 Access to multiple shared resources can be
centrally granted
 Optimized to handle heavy processing loads
and dedicated to handling requests from
clients
 Can connect more than a handful of
computers
Wide Area Network (WAN)
(Except T118, Coach House LANs have access to WAN/Internet)
 Network
connecting two
or more
geographically
distinct LANs
– The Internet is
an intricate and
extensive WAN
spanning the
globe
FIGURE 1-5 A simple WAN
Elements Common to All
Server-Based Networks
 Client
– Also refers to the human user of a client
workstation
 Server
 Workstation
Elements Common to All
Server-Based Networks
 Network
Interface Card
(NIC)
– Device that
enables a
workstation to
connect to the
network
(usually preinstalled and
comes as an
integrated part
of a PC or
workstation.)
FIGURE 1-7 A network interface card (NIC)
Elements Common to All
Server-Based Networks
 NOS (Network Operating System)
 Host (Server in server room; Coach House
has several servers)
– Server that manages shared resources
 Node
– Any client, server, or other device on a network
identified by a unique identifying number
Elements Common to All
Server-Based Networks
 Topology
– Physical
layout of a
computer
network
FIGURE 1-7 Commonly used network topologies
Elements Common to All
Server-Based Networks
 Protocol
– Rules the network uses to transfer data; TCP/IP is the protocol for
the Internet.
– Data Packets: a message or file is broken down into small
segments (known as packet); packets are transmitted and routed
through the network individually in order to gain efficiency (higher
utilization of the transmission media).
– The distinct units of data transmitted from one computer on a
network to another
 Addressing (will be discussed in more details in
later chapters)
– Scheme for assigning a unique identifying number to every
workstation or PC on a network
– The number that uniquely identifies each workstation or device on
a network is its address.
Elements Common to All
Server-Based Networks
 Transmission
Media
– Means through
which data is
transmitted and
received
– For LAN, twisted
pair is the most
common.
FIGURE 1-8 Examples of network transmission media
How Networks Are Used
 Services
– Features provided by a network
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File and Print Services
Communications Services
Mail Services
Internet Services
Management Services
Network Services
 File Services
– Allow users to share data files, applications,
and disk storage space
 Communications Services
– Allow remote users to connect to a network
• Remote User
– Person working on a computer in a different geographical
location from the LAN’s server
• Communications Server
– Access Server
Network Services
 Mail Services
– Coordinate the storage and transfer of e-mail
between users on a network
• Gateway
– Combination of software and hardware enabling two
different kinds of networks to exchange data
 Internet Services
– Enable a network to communicate with the
Internet
Network Services
 Management Services
– Centrally administer and simplify complicated
management tasks on the network
– Numerous services fall under category of network
management
– You as a network administrator will learn how to
perform various administration tasks.
Important Management Services
 Traffic Monitoring and Control
– Traffic Data transmission and processing activity taking
place on a computer network at any given time
– Segment
• Part of a LAN separated from other parts of the LAN and that
shares
 Load Balancing
– Distributing process activity evenly across a network so
that no single device is overwhelmed
These tasks are not a critical for our Coach House
network; we have ample capacity to handle
relatively light traffic.
Important Management Services
 Hardware Diagnosis and Failure Alert
 Asset Management
– Collecting and storing data on the number and types of
software and hardware assets in an organization’s
network
 License Tracking
– Determining how many copies of an application are
currently in use on a network
Coach House main Unix server hardware is covered by
service contract. We do need to track the license and
document the asset (equipment list distributed to all)
Important Management Services
 Security Auditing
– Evaluating security measures currently in place
on a network and notifying the network
administrator if a security breach occurs
 Software Distribution
– Process of automatically transferring a data file
or program from the server to a client on the
network
We have good track record!
Important Management Services
 Address Management (Managed by the
University; procedures on WPUNJ Web site)
– Centrally administering a finite number of network
addresses for an entire LAN
 Backup and Restoration of Data
– Backing Up
• Copying critical files to a secure storage area
– Restoring
• Retrieving data if original files are lost
 Very critical especially the system related files in
the event the system crashes!
Becoming a Network
Professional
 Mastering the Technical Challenges
 Developing Your “Soft Skills”
 Pursuing Certification
 Finding a Job in Networking
 Joining Professional Associations
Mastering the Technical
Challenges
 Installing, configuring, and troubleshooting
network file server software
 Installing, configuring, and troubleshooting
network file server hardware
 Installing, configuring, and troubleshooting
network client software
 Installing, configuring, and troubleshooting
network client hardware
Mastering the Technical
Challenges
 Understanding the characteristics of
different transmission media
 Understanding network design
 Understanding network protocols
 Understanding how users interact with the
network
Mastering the Technical
Challenges
 Specialty areas in high demand for
networking professionals:
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Network security
Internet and intranet design
Network management
Voice/data integration
Remote and mobile computing
Mastering the Technical
Challenges
 More specialty areas:
– Data integrity and fault tolerance
– In-depth knowledge of Microsoft networking
products
– In-depth knowledge of NetWare networking
products
– In-depth knowledge of router configuration and
management
Developing Your “Soft Skills”
 Skills not easily measured but important to
a networking career:
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Customer Relations
Oral and Written Communications
Dependability!!!
Teamwork!!!
Leadership Abilities
Pursuing Certification
 Certification
– Process of mastering material pertaining to a
particular hardware system, operating system,
programming language, or other program, then
proving your mastery by passing a series of
exams
 Computer Technology Association
(CompTIA)
Pursuing Certification
 A+
 Microsoft Certified Systems Engineer
(MCSE)
 Certified NetWare Engineer (CNE)
 Net+
Web Sites
TABLE 1-1
Web sites
with job
databases
Professional Association Sites
TABLE 1-2
Web sites of
networking
organizations
Chapter Summary
 A Network is a group of computers or other
devices connected by some type of
transmission media
 Networks may be small or large, connecting
computers in one office or across the world
 All networks offer advantages relative to the
use of standalone computers
Chapter Summary
 A LAN is a network of computers and other devices




confined to a relatively small space
A WAN is a network connecting two or more
geographically distinct LANs
All server-based networks share some common
elements
The physical layout of a computer network is called a
topology
Network protocols are the rules that the network uses
to transfer data
Chapter Summary
 File and print services provide the foundation for
networking
 Mail services allow networks users to exchange and
store e-mail
 Internet services enable organizations to connect to the
Internet
 Network management services centrally administer
and simplify complicated management tasks on the
network
Chapter Summary
 Networking professionals are in demand
 Certification
 Hone your soft skills
 Numerous resources are available in
searching for networking positions
 Joining associations can benefit your
professional growth