Chapter 1: Introduction to
Networking
Objectives
List the advantages of networked computing
relative to standalone computing
Distinguish between client/server and peer-topeer networks
List elements common to all client/server
networks
Objectives (continued)
Describe several specific uses for a network
Identify some of the certifications available to
networking professionals
Identify the kinds of non-technical, or “soft,”
skills that will help you succeed as networking
professional
A Network is:
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A group of computers and other devices (such as printers)
that are connected by some type of transmission media, such
as copper or fiber-optic cable or the atmosphere, in the case
of wireless transmission.
As small as two computers connected by a cable in a home
office or as large as several thousand computers connected
across the world via a combination of cable, phone lines, and
satellite links.
Connecting personal computers, networks may link
mainframe computers, printers, plotters, fax machines, and
phone systems.
Why Use Networks?
• Manage or Administer resources on multiple
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computers from a central location
Networks—enable multiple users to share
devices and resources such as:
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Printers
Faxes
Programs and Files
• Word Processing
• Spread Sheets
• Data Base
Types of Networks
• Peer-to-peer Networks
• Client/Server Networks
Peer-to-peer Networks
• Simple to configure
• Don’t need much technical expertise
• Typically less expensive to setup
• Suitable for environments where saving
money is critical
• Not very flexible
Peer-to-peer Networks (continued)
Client/Server Networks
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Servers facilitate communication and resource sharing
between other computers on the network known as
clients
Networks that use a server to enable clients to share
data, data storage space, and devices is known as a
client/server network
Computers on a client/server network act as a client or
a server
To function as a server, a computer must be running a
network operating system (NOS), a special type of
software designed to manage data and other resources
for a number of clients
Client/Server Network (continued)
Advantages Over
Peer-to-Peer Networks
• Client Servers offer:
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User login accounts and passwords for anyone on a
server-based network can be assigned in one place
Access to multiple shared resources (such as data
files or printers) can be centrally granted to a single
user or groups of users
Problems on the network can be tracked, diagnosed,
and often fixed from one location
Advantages Over
Peer-to-Peer Networks (continued)
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Servers are optimized to handle heavy processing
loads and dedicated to handling requests from
clients, enabling faster response time
Because of their efficient processing and larger disk
storage, servers can connect more than a handful of
computers on a network
LANs, MANs, and WANs
• LAN – Local Area Network
• MAN – Metropolitan Area Network
• WAN – Wide Are Network
Local Area Network (LAN)
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A network of computers and other devices
that is confined to a relatively small space,
such as one building or even one office
• Interconnected and rely on several servers
running many different applications and
managing resources other than data
Complex Network
Metropolitan Area
Network (MAN)
• A network that is larger than a LAN and
connects clients and servers from multiple
buildings
• A MAN may use different transmission
technology and media than a LAN because of
the distance it covers
Wide Area Network (WAN)
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A network that connects two or more geographically
distinct LANs or MANs
WANs carry data over longer distances than LANs
WANs require slightly different transmission methods
and media and often use a greater variety of
technologies than LANs
Most MANs can also be described as WANs
WANs commonly connect separate offices in the same
organization, whether they are across town or across the
world from each other
Wide Area Network (WAN)
(continued)
Elements Common To All Client
Server Networks
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Client. A computer on the network that requests
resources or services from another computer on a
network. In some cases, a client could also act as a
server. he term “client” may also refer to the human
user of a client workstation
Server. A computer on the network that manages shared
resources and usually have more processing power,
memory, and hard disk space than clients. They run
network operating software that can manage not only
data, but also users, groups, security, and applications
on the network
Elements Common To All Client
Server Networks (continued)
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Workstation. A desktop computer, which may or may
not be connected to a network. Most clients are
workstation computers
Elements Common To All Client
Server Networks (continued)
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Network interface card (NIC). The device inside a
computer that connects a computer to the network
media, thus allowing it to communicate with other
computers. Several companies (such as 3Com, IBM,
Intel, SMC, and Xircom) manufacture NICs, which come
with a variety of specifications that are tailored to the
requirements of the workstation and the network. NICs
are also known as network adapters
Elements Common To All Client
Server Networks (continued)
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Network operating system (NOS). The software that
runs on a server and enables the server to manage data,
users, groups, security, applications, and other
networking functions
The most popular network operating systems are
Microsoft Windows Server 2003, Novell NetWare, and
UNIX
Elements Common To All Client
Server Networks (continued)
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Host. A computer that enables resource sharing by other
computers on the same network.
Node. A client, server, or other device that can
communicate over a network and that is identified by a
unique number, known as its network address
Elements Common To All Client
Server Networks (continued)
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Topology. The physical layout of a computer network.
Topologies vary according to the needs of the
organization and available hardware and expertise.
Networks are usually arranged in a ring, bus, or star
formation; hybrid combinations of these patterns are also
possible
Network Topologies
Elements Common To All Client
Server Networks (continued)
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Connectivity device. One of several types of
specialized devices that allows two or more networks or
multiple parts of one network to connect and exchange
data
Protocol. A pre-determined method or format for
exchanging data between computers. Protocols ensure
that data are transferred whole, in sequence, and without
error from one node on the network to another. To
maintain and manage a network effectively, you must
have a thorough understanding of network protocols
Elements Common To All Client
Server Networks (continued)
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Data packets. The distinct units of data that are
transmitted from one computer on a network to another.
Breaking a large stream of data into many packets
allows a network to deliver that data more efficiently and
reliably
Elements Common To All Client
Server Networks (continued)
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Addressing. The scheme for assigning a unique
identifying number to every workstation and device on
the network
Transmission media. The means through which data is
transmitted and received. Transmission media may be
physical, such as wire or cable, or atmospheric
(wireless), such as radio waves
Elements Common To All Client
Server Networks (continued)
How Networks Are Used
• Functions provided by a network are usually
referred to as network services
• File and Print Services
• File services: share data files, applications and disk
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storage space
Print services: share printers across a network
• Communications Services
• Allow remote users to connect to the network
How Networks Are Used
(continued)
• Mail Services
• Intercept or filter unsolicited e-mail
• Find objectionable content
• Route messages according to particular rules
• Provide a Web-based client for checking e-mail
• Notify if certain events occur
• Schedule e-mail transmission, retrieval, storage, and
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maintenance functions
Communicate with mail servers on other networks
How Networks Are Used
(continued)
• Internet Services
• Web server to supply Web pages upon demand
• Other Internet services include:
• file transfer
• Internet addressing schemes
• security filters
• means for directly logging on to other computers
How Networks Are Used
(continued)
• Management Services
• Centrally administer management tasks on the
network
• Traffic monitoring and control
• Load balancing
• Hardware diagnosis and failure alert
• Asset management
• License tracking
How Networks Are Used
(continued)
• Centrally administer management tasks on the
network (cont.)
• Security auditing
• Software distribution
• Address management
• Backup and restoration of data
Becoming a Network
Professional
• Mastering the Technical Challenges
• Acquire these skills:
• Installing, configuring, and troubleshooting network
• Server and Client software and hardware
• Understanding different transmission media
• Understanding network design
• Understanding network protocols
• Understanding how users interact with the network
• Constructing a network with clients, servers, media,
and connectivity devices
Becoming a Network Professional
(continued)
• Mastering the Technical Challenges (cont.)
• Specialties in high demand:
• Network security
• Voice/data integration
• In-depth knowledge about one or more NOSs
• Network management
• Internet and intranet design
• Configuration and optimization of routers and switches
• Centralized data storage and management for largescale environments
Becoming a Network Professional
(continued)
• Developing Your “Soft Skills”
• Customer relations
• Oral and written communications
• Dependability
• Teamwork
• Leadership abilities
Becoming a Network Professional
(continued)
• Pursuing Certification
• Benefits to becoming certified:
• Better salary
• Greater opportunities
• Professional respect
• Access to better support
Becoming a Network Professional
(continued)
• Finding a Job in Networking
• Search the Web
• Classified ad section of local newspaper
• Visit a career center
• Network with like-minded professionals
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Attend career fairs
Enlist a recruiter
Becoming a Network Professional
(continued)
• Joining Professional Associations
• Association for Computing Machinery (ACM)
• www.acm.org
• Association for Information Technology Professionals
• www.aitp.org
• Chinese Information and Networking Association
• www.cina.org
Becoming a Network Professional
(continued)
• IEEE Computer Society
• www.computer.org
• Women in Technology International (WITI)
• www.witi.org
Summary
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Network is a group of computers and other devices
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Networks offer advantages
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Peer-to-peer network, every computer can
communicate directly with every other computer
Traditional peer-to-peer networks consist of two or
more personal computers
Summary (continued)
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Traditional peer-to-peer networks are usually simple
and inexpensive
Client/server networks rely on a centrally
administered server
Client/server networks are more complex and
expensive
Servers typically possess more processing power,
hard disk space, and memory
Summary (continued)
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Local area network (LAN) is a network of computers
and other devices
LANs can be connected to form wide area networks
(WANs)
All client/server networks share some common
elements
Summary (continued)
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Networks provide services for e-mail, printing, file
sharing, Internet access, remote access capabilities,
and network management
File and print services provide the foundation for
networking
Networks use communications services to allow
remote users to connect
Summary (continued)
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Mail services allow users on a network to exchange
and store e-mail
Internet services enable organizations to connect to
and use the global Internet
Network management services
Summary (continued)
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Prepare yourself for a networking career
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Certification is the process of mastering material
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Hone your soft skills
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Joining an association for networking professionals