Download Before You Begin: Assign Information Classification

Chapter 8:
Networks
IT Essentials: PC Hardware and Software v4.0
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
1
Purpose of this Presentation
To provide to instructors an overview of Chapter 8:
 List of chapter objectives
 Overview of the chapter contents, including
student worksheets
student activities
student labs
 Reflection/Activities for instructors to complete to
prepare to teach
 Additional resources
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
2
Chapter 8 Objectives
 8.1 Explain the principles of networking
 8.2 Describe types of networks
 8.3 Describe basic networking concepts and technologies
 8.4 Describe the physical components of a network
 8.5 Describe LAN topologies and architectures
 8.6 Identify standards organizations
 8.7 Identify Ethernet standards
 8.8 Explain OSI and TCP/IP data models
 8.9 Describe how to configure a NIC and a modem
 8.10 Identify names, purposes, and characteristics of other
technologies used to establish connectivity
 8.11 Identify and apply common preventive maintenance techniques
used for networks
 8.12 Troubleshoot a network
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
3
Chapter 8 Worksheets, Activities, and Labs
 8.1.2 Activity: Advantages and Disadvantages of
Networking
 8.2.3 Activity: Network Types
 8.3.2 Worksheet: Identify IP Address Classes
 8.3.4 Activity: Network Protocols
 8.8.3 Activity: OSI Model
 8.9.1 Worksheet: Internet Search for NIC Drivers
 8.9.2 Lab: Configure an Ethernet NIC to use DHCP
 8.10.3 Worksheet: Answer Broadband Questions
 8.12.2 Worksheet: Diagnose a Network Problem
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
4
Introduction
 Chapter 8 is an overview of network principles,
standards, and purposes
 It covers the following types of networks:
Local Area Network (LAN)
Wide Area Network (WAN)
Wireless LAN (WLAN)
 These topics are covered:
Network topologies, protocols, and logical models
Hardware needed to create a network
Configuration, troubleshooting, and preventive maintenance
Network software, communication methods, and hardware
relationships
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
5
Principles of Networking
 Networks are systems that are formed by links.
 People use different types of networks every day:
Mail delivery system
Telephone system
Public transportation system
Corporate computer network
The Internet
 Computers can be linked by networks to share data and
resources.
 A network can be as simple as two computers
connected by a single cable or as complex as hundreds
of computers connected to devices that control the flow
of information.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
6
Computer Networks
 Network devices include:
Desktop and laptop computers
Printers and scanners
PDAs and Smartphones
File and print servers
 Resources shared across networks include:
Services, such as printing or scanning
Storage devices, such as hard drives or optical drives
Applications, such as databases
 Different types of network media:
Copper cabling
Fiber-optic cabling
Wireless connection
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
7
Benefits of Networking
 Fewer peripherals
needed
 Increased
communication
capabilities
 Avoid file duplication
and corruption
 Lower cost licensing
 Centralized
administration
 Conserve resources
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
8
Types of Networks
A computer network is
identified by:
 The area it serves
 How the data is stored
 How the resources are
managed
 How the network is
organized
 The type of networking
devices used
 The type of media used
to connect the devices
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
9
Local Area Network (LAN)
 A group of interconnected
computers that is under the
same administrative control.
 Can be as small as a single
local network installed in a
home or small office.
 Can consist of
interconnected local
networks consisting of
many hundreds of hosts,
installed in multiple
buildings and locations.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
10
Wide Area Network (WAN)
 A WAN connects LANs in geographically separated
locations.
 A WAN covers a much larger
area than a LAN.
The Internet is a large WAN.
 Telecommunications service
providers (TSP) are used to
interconnect these LANs at
different locations.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
11
Wireless LAN (WLAN)
 Wireless devices are used to transmit and receive
data using radio waves.
 Wireless devices connect to access points within a
specified area.
 Access points connect to the
network using copper cabling.
 WLAN coverage can be
limited to the area of a
room, or can have greater
range.
 You can share resources
such as files and printers,
and access the Internet on
a WLAN.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
12
Peer-to-Peer Networking
 Share files, send messages, and print to a shared printer.
 Each computer has similar capabilities and
responsibilities.
 Each user decides which data and devices to share.
 No central point of control in the network.
 Best if there are ten or fewer computers.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
13
Disadvantages of Peer-to-Peer
 Without centralized network administration, it is difficult
to determine who controls network resources.
 Without centralized security, each computer must use
separate security measures for data protection.
 More complex and difficult to manage as the number
of computers on the network increases.
 Without centralized data storage, data backups must
be performed by users.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
14
Client/Server Network
 Client/server network model provides security and
control for the network.
 Client requests information or services from the server.
 Server provides the requested information or service.
 Servers are maintained by network administrators.
Data backups and security measures
Control of user access to network resources
 Centralized storage and services include:
Data stored on a centralized file server
Shared printers managed by a print server
Users have proper permissions to access data or printers
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
15
Networking Concepts and Technologies
 A computer technician is required to configure and
troubleshoot computers on a network.
 A computer technician should understand IP
addressing, protocols, and other network concepts.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
16
Bandwidth
 amount of data that can
be transmitted within a
fixed time period
 measured in bits per
second and is usually
denoted by the following:
bps - bits per second
Kbps - kilobits per
second
Mbps - megabits per
second
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
17
Three Modes of Transmission
Data is transmitted in one of three modes:
1. Simplex (Unidirectional transmission) is a single, oneway transmission.
Example: The signal sent from a TV station to your TV.
2. Half-duplex allows data to flow in one direction at a
time.
Simultaneous transmission in two directions is not allowed.
Example: Two-way radios, police or emergency mobile radios
3. Full-duplex allows data to flow in both directions at
the same time.
Bandwidth is measured in only one direction. 100 Mbps fullduplex means a bandwidth of 100 Mbps in each direction.
Broadband technologies, such as digital subscriber line (DSL)
and cable, operate in full-duplex mode.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
18
IP Address
 An IP address is a unique number that is used to identify
a network device.
 An IP address is represented as a 32-bit binary number,
divided into four octets (groups of eight bits):
Example: 10111110.01100100.00000101.00110110
 An IP address is also represented in a dotted decimal
format.
Example: 190.100.5.54
 When a host is configured with an IP address, it is
entered as a dotted decimal number, such as
192.168.1.5.
 Unique IP addresses on a network ensure that data can
be sent to and received from the correct network device.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
19
IP Address Classes
 Class A
Large networks, implemented by large companies and some
countries
 Class B
Medium-sized networks, implemented by universities
 Class C
Small networks, implemented by ISP for customer subscriptions
 Class D
Special use for multicasting
 Class E
Used for experimental testing
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
20
Subnet Masks
 Used to indicate the network portion of an IP address
 Is a dotted decimal number
 Usually, all hosts within a broadcast domain of a LAN
(bounded by routers) use the same subnet mask.
 The default subnet masks for three classes of IP
addresses:
255.0.0.0 is the subnet mask for Class A
255.255.0.0 is the subnet mask for Class B
255.255.255.0 is the subnet mask for Class C
 If an organization owns one Class B network but needs to
provide IP addresses for four LANs, the organization will
subdivide the Class B network into four smaller parts by
using subnetting, which is a logical division of a network.
The subnet mask specifies how it is subdivided.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
21
IP Address Configuration
 Manual configuration
Manually configure each device with the proper IP address and
subnet mask.
 Dynamic configuration
A Dynamic Host Configuration Protocol (DHCP) server
automatically assigns IP addresses to network hosts.
 Network Interface Card (NIC) is the hardware that
enables a computer to connect to a network and it has
two addresses:
The IP address is a logical address that can be changed.
The Media Access Control (MAC) address is "burned-in" or
permanently programmed into the NIC when manufactured.
The MAC address cannot be changed.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
22
Dynamic Host Configuration Protocol
(DHCP)
 DHCP automatically
provides computers with an
IP address.
 The DHCP server can
assign these to hosts:
IP address
Subnet mask
Default gateway
Domain Name System (DNS)
server address
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
23
DHCP Process and Advantages
DHCP process:
1. DHCP server receives a request from a host.
2. Server selects IP address information from a
database.
3. Server offers the addresses to requesting host.
4. If the host accepts the offer, the server leases the IP
address for a specific period of time.
Advantages of DHCP:

Simplifies the administration of a network

Reduces the possibility of assigning duplicate or
invalid addresses
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
24
Configure Host to Use DHCP
Configure the host to "Obtain an IP address automatically"
in the TCP/IP properties of the NIC configuration
window
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
25
Internet Protocols
 A protocol is a set of rules.
 Internet protocols are sets of rules governing
communication within and between computers on a
network.
 Many protocols consist of a suite (or group) of protocols
stacked in layers. These layers depend on the operation
of the other layers in the suite to function properly.
 The main functions of protocols:
Identifying errors
Compressing the data
Deciding how data is to be sent
Addressing data
Deciding how to announce sent and received data
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
26
Common Network Protocols
Protocols used for browsing the web, sending and receiving
e-mail, and transferring data files
Description
TCP/IP
NETBEUI
NETBIOS
IPX and SPX
HTTP and HTTPS
A small, fast protocol designed for a workgroup network that
requires no connection to the Internet.
A protocol used to transport data on a Novell Netware network.
A protocol that defines how files are exchanged on the Web.
FTP
A protocol that provides services for file transfer and manipulation.
SSH
A protocol that is used to connect computers together securely.
Telnet
ITE PC v4.0
Chapter 5
A protocol used to transport data on the Internet.
A protocol that uses a text-based connection to a remote
computer.
POP
A protocol used to download email messages from an email
server.
IMAP
A protocol used to download email messages from an email
server.
SMTP
A protocol used to send mail in a TCP/IP network.
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
27
Internet Control Message Protocol (ICMP)
 Internet Control Message Protocol (ICMP) is used by
devices on a network to send control and error
messages to computers and servers.
 PING (Packet Internet Groper) is a simple command
line utility used to test connections between computers
Used to determine whether a specific IP address is accessible.
Used with either the hostname or the IP address.
Works by sending an ICMP echo request to a destination
computer.
Receiving device sends back an ICMP echo reply message.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
28
Ping Command Switches
These command line switches (options) can be used
with the ping command.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
29
Output of the Ping Command
 Four ICMP echo requests (pings) are sent to the
destination computer to determine the reliability and
reachability of the destination computer.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
30
Physical Network Components
 Network devices:
Computers
Hubs
Switches
Routers
Wireless access points
 Network media:
Twisted-pair copper cabling
Fiber-optic cabling
Radio waves
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
31
Hubs
 Extend the range of a signal by receiving then
regenerating it and sending it out all other ports
 Traffic is sent out all ports of the hub
 Allow a lot of collisions on the network segment and
are often not a good solution
 Also called concentrators because they serve as a
central connection point for a LAN
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
32
Bridges and Switches
 A packet, along with its MAC address information, is
called a frame.
 LANs are often divided into sections called segments
bounded by bridges.
 A bridge has the intelligence to determine if an
incoming frame is to be sent to a different segment, or
dropped. A bridge has two ports.
 A switch (multiport bridge)
has several ports and refers
to a table of MAC addresses
to determine which port to
use to forward the frame.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
33
Routers
 Routers are devices that connect entire networks to
each other.
Use IP addresses to forward packets to other networks.
Can be a computer with special network software installed.
Can be a device built by network equipment manufacturers.
Contain tables of IP addresses along with optimal routes to
other networks.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
34
Wireless Access Points
 Provide network access to
wireless devices such as
laptops and PDAs.
 Use radio waves to
communicate with radios in
computers, PDAs, and other
wireless access points.
 Have limited range of
coverage.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
35
Multipurpose Devices
 Perform more than one function.
 More convenient to purchase and
configure just one device.
 Combines the functions of a switch,
a router and a wireless access point
into one device.
 The Linksys 300N is an example of a
multipurpose device.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
36
Twisted-Pair Cabling
 A pair of twisted wires forms a circuit that transmits data.
 The twisted wires provide protection against crosstalk
(electrical noise) because of the cancellation effect.
Pairs of copper wires are encased
in color-coded plastic insulation
and twisted together.
An outer jacket, called poly-vinyl
chloride (PVC), protects the
bundles of twisted pairs.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
37
Two Basic Types of Twisted-Pair Cables
 Unshielded twisted-pair (UTP)
Has two or four pairs of wires
Relies on the cancellation effect for reduction of interference
caused by electromagnetic interface (EMI) and radio
frequency interference (RFI)
Most commonly used cabling in networks
Has a range of 328 ft (100 meters)
 Shielded twisted-pair (STP)
Each pair is wrapped in metallic foil to better shield the wires
from electrical noise and then the four pairs of wires are then
wrapped in an overall metallic braid or foil.
Reduces electrical noise from within the cable.
Reduces EMI and RFI from outside the cable.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
38
Category Rating
 UTP comes in several categories that are based on two
factors:
The number of wires in the cable
The number of twists in those wires
 Category 3 is used for telephone connections.
 Category 5 and Category 5e have are the most
common network cables used.
 Category 6 cable has higher data rate than the Cat 5
cables.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
39
Coaxial Cable
 A copper-cored network cable surrounded by a heavy
shielding
 Types of coaxial cable:
Thicknet or 10Base5 - Coax cable that was used in networks
and operated at 10 megabits per second with a maximum
length of 500 m
Thinnet or 10Base2 - Coax cable that was used in networks
and operated at 10 megabits per second with a maximum
length of 185 m
RG-59 - Most commonly used for cable television in the US
RG-6 - Higher quality cable than RG-59 with more bandwidth
and less susceptibility to interference
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
40
Fiber-Optic Cable
 A glass or plastic strand that transmits
information using light and is made up of
one or more optical fibers enclosed
together in a sheath or jacket.
 Not affected by electromagnetic or radio
frequency interference.
 Signals are clearer, can go farther, and
have greater bandwidth than with copper
cable.
 Usually more expensive than copper
cabling and the connectors are more
costly and harder to assemble.
 Two types of glass fiber-optic cable:
Multimode and Single-mode
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
41
Two Types of LAN Topologies
Physical topology is the
physical layout of the
components on the
network
Logical topology
determines how the hosts
access the medium to
communicate across the
network
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
42
LAN Physical Topologies
A physical topology defines the way in which computers,
printers, and other
devices are
connected to a
network.
 Bus
 Ring
 Star
 Hierarchical star
 Mesh
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
43
Bus Topology
 Each computer connects to a common cable
 Cable connects one computer to the next
 Ends of the cable have a terminator installed to
prevent signal reflections and network errors
 Only one computer can transmit data at a time or
frames will collide and be destroyed
 Bus topology is rarely used today. Possibly suitable for
a home office or small business with few hosts
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
44
Ring Topology
 Hosts are connected in a physical ring or circle.
 The ring has no beginning or end, so the cable does not
need to be terminated.
 A special frame, a token, travels around the ring,
stopping at each host.
 The advantage of a ring
topology is that there are no
collisions.
 There are two types of ring
topologies:
Single-ring and Dual-ring
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
45
Star Topology
 Has a central connection
point: a hub, switch, or
router
 Hosts connect directly to
the central point with a
cable
 Costs more to implement than the bus topology
because more cable is used, and a central device is
needed
 Easy to troubleshoot, since each host is connected to
the central device with its own wire.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
46
Hierarchical or Extended Star Topology
 A star network with an additional networking device
connected to the main networking device to increase
the size of the network.
 Used for larger networks
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
47
Mesh Topology
 Connects all devices to each other
 Failure of any cable will not affect the network
 Used in WANs that interconnect LANs
 Expensive and difficult to
install because of the
amount of cable needed
 The Internet is an example
of a mesh topology
 Often used by governments
when data must be
available in the event of a
partial network failure
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
48
Logical Topologies
The two most common types of logical topologies are
broadcast and token passing.
 In a broadcast topology, there is no order that the
hosts must follow to use the network – it is first come,
first served for transmitting data on the network.
 Token passing controls network access by passing an
electronic token sequentially to each host. When a host
receives the token, it can send data on the network. If
the host has no data to send, it passes the token to the
next host and the process repeats itself.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
49
LAN Architecture
 Is the overall structure of a computer or communication
system.
 Designed for a specific use and have different speeds
and capabilities.
 Describes both the physical and logical topologies used
in a network.
 The three most common LAN architectures:
Ethernet
Token Ring
Fiber-Distributed
Data Interface (FDDI)
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
50
Ethernet
 Based on the IEEE 802.3 standard, which specifies
that a network use the Carrier Sense Multiple Access
with the Collision Detection (CSMA/CD) access control
method.
Hosts access the network using the first come, first served
broadcast topology method to transmit data.
 Standard transfer rates
10 Mbps (Ethernet) “10Base-T”
100 Mbps (FastEthernet) “100Base-T”
1000 Mbps = 1 Gbps (Gigabit Ethernet) “1000Base-T”
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
51
Token Ring
 Reliable network architecture
 Originally developed by IBM
 Based on the token-passing
access control method
 Often integrated with IBM
mainframe systems
 Used with smaller computers
and mainframes
 Physically, a star-wired ring
because the outer appearance
of the network design is a star
 Inside the device, wiring forms a
circular data path, creating a
logical ring
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
52
Fiber Distributed Data Interface (FDDI)
 A type of Token Ring network
 Often used for LANs, connecting several buildings in
an office complex or on a university campus
 Runs on fiber-optic cable
 High-speed performance combined with token-passing
advantage
 Runs at 100 Mbps with a primary and secondary ring
topology
 Normally, traffic flows only on the primary ring and uses
a secondary ring is a backup.
 FDDI dual ring supports up to 500 computers per ring
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
53
Standards Organizations
ITU-T
Name
Type
Standards
Established
ITU Telecommunication
Standardization Sector
one of the three
Sectors of the
International
Telecommunication
Union
Standards covering all
fields of
telecommunications
Became ITU-T in
1992
Institute of Electrical and
Electronics Engineers
A non-profit,
technical
professional
association
Standards for the
computer and electronics
industry
1884
International Organization
for Standardization
A network of the
national standards
institutes of 157
countries
Promote the development
of international standards
agreements
1947
1979; first named
ICCB
(formerly CCITT)
IEEE
ISO
IAB
Internet Architecture Board
A committee; an
advisory body
Oversees the technical
and engineering
development of the
Internet
IEC
International
Electrotechnical
Commission
Global organization
Standards for all
electrical, electronic, and
related technologies
1906
American National
Standards Institute
Private, non-profit
organization
Seeks to establish
consensus among
groups
1918
Standards for voice and
data wiring for LANs
After the
deregulation of the
U.S. telephone
industry in 1984
ANSI
TIA/EIA
ITE PC v4.0
Chapter 5
Telecommunications
Industry Association /
Electronic Industries
Alliance
© 2006 Cisco Systems, Inc. All rights reserved.
Trade associations
Cisco Public
54
Ethernet Standards
Ethernet protocols describe the rules
that control how communication
occurs on an Ethernet network.
 The 802.2 standard defines how a
device addresses other devices on
the medium.
 The 802.3 standard defines the
methodology that devices must
use when they use the media.
 The 802.11x standards define how
wireless devices communicate
using radio waves.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
55
Cabled Ethernet Standards
 IEEE 802.3 Ethernet standard specifies that a network implement
the CSMA/CD access control method.
 In CSMA/CD operation:
All end stations "listen" to the network wire for clearance to
send data.
When the end station detects that no other host is transmitting,
the end station will attempt to send data.
If no other station sends any data at the same time, this
transmission will arrive at the destination computer
successfully.
If another end station transmits at the same time, a collision will
occur on the network media.
The first station that detects the collision, sends out a jam
signal to tell all stations to stop transmitting and to run a backoff
algorithm.
All stations stop transmitting and re-try after a random period of
time.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
56
10BASE-T
 10BASE-T is an Ethernet technology that uses a star
topology.
The ten (10) represents a speed of 10 Mbps.
BASE represents baseband transmission.
The T represents twisted-pair cabling.
 Advantages of 10BASE-T:
Installation is inexpensive compared to fiber-optic installation.
Cables are thin, flexible, and easier to install than coaxial
cabling.
Equipment and cables are easy to upgrade.
 Disadvantages of 10BASE-T:
The maximum length for a 10BASE-T segment is 328 ft (100 m).
Cables are susceptible to Electromagnetic Interference (EMI).
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
57
100BASE-TX “FastEthernet”
 Has a theoretical bandwidth of 100 Mbps.
 The "X" indicates different types of copper and fiber-optic
can be used.
 Advantages of 100BASE-TX:
Transfer rates of 100BASE-TX are ten times that of 10BASE-T
100BASE-X uses twisted-pair, inexpensive and easy to install
 Disadvantages of 100BASE-TX:
Maximum length for a 100BASE-TX segment is 329 ft (100 m).
Cables are susceptible to Electromagnetic Interference (EMI).
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
58
1000BASE-TX “Gigabit Ethernet”
 Advantages of 1000BASE-T:
1 Gbps is ten times faster than Fast Ethernet and 100 times
faster than Ethernet.
Increased speed makes it possible to implement bandwidthintensive applications, such as live video.
The 1000BASE-T architecture has interoperability with 10BASET and 100BASE-TX.
 Disadvantages of 1000BASE-T:
Maximum length for a 1000BASE-T segment is 328 ft (100 m).
It is susceptible to interference.
Gigabit NICs and Switches are expensive.
Additional equipment is required.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
59
Wireless Ethernet Standards
 IEEE 802.11 is the standard that specifies connectivity
for wireless networks.
 Wi-Fi (wireless fidelity), refers to the 802.11 family
802.11 (the original specification)
802.11b
802.11a
802.11g
802.11n
These protocols specify the frequencies, speeds, and other
capabilities of the different Wi-Fi standards.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
60
IEEE 802.11a WLAN Standard
 Allows data rates as high as 54 Mbps
 Devices operate in the 5 GHz radio frequency range
 Avoids some interference issues of 802.11b
 802.11a is not backward compatible to 802.11b
 Dual mode wireless NICs are available
 802.11a has a range of approximately 100 ft (30 m)
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
61
IEEE 802.11b WLAN Standard
 Operates in the 2.4 GHz frequency range
 Maximum theoretical data rate of 11 Mbps, but typically
about 6.5 Mbps
 Average range of approximately 100 ft (30 m) at 11
Mbps and 295 ft (90 m) at 1 Mbps
 Range fluctuates depending on the operational speed.
 Signal quality dictates the operational speed of 802.11b.
 Bluetooth devices, cordless phones, and even
microwave ovens operate in the 2.4 GHz band, possibly
causing interference.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
62
IEEE 802.11g and 802.11n
 802.11g
Allows data rates as high as 54 Mbps
Operates in the same 2.4 GHz spectrum as 802.11b
802.11g is backward compatible with 802.11b
Interoperability among all speeds (a, b, g) exists
Average range of approximately 100 ft (30 m)
 802.11n
Has a theoretical bandwidth of 540 Mbps
Operates in either the 2.4 GHz or 5 GHz frequency range
Maximum range of 164 ft (50 m)
Expected approval for 802.11n is April 2008 or earlier
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
63
Wireless Ethernet Standards
Bandwidth Frequency
Range
Interoperability
Not interoperable with
802.11b, 802.11g, or
802.11n
802.11a
Up to 54
Mbps
5 GHz band
100 feet
(30 meters)
802.11b
Up to 11
Mbps
2.4 GHz band
100 feet
(30 meters)
Interoperable with
802.11g
802.11g
Up to 54
Mbps
2.4 GHz band
100 feet
(30 meters)
Interoperable with
802.11b
802.11n
Up to 540
Mbps
2.4 GHz band
164 feet
(50 meters)
Interoperable with
802.11b and 802.11g
(Pre-standard)
802.15.1
Bluetooth
ITE PC v4.0
Chapter 5
2.4 GHz band
30 feet
Up to 2 Mbps
or 5 GHz
(10 meters)
band
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
Not interoperable with
any other 802.11
64
OSI and TCP/IP Data Models
 Architectural model
Separates functions of protocols into manageable layers
Each layer performs a specific function in network
communication
 TCP/IP model
A four-layer model that explains the TCP/IP suite of protocols
TCP/IP is the dominant standard for transporting data across
networks
 Open Systems Interconnect (OSI) model
Standards defining how devices communicate on a network
Ensures interoperability between network devices
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
65
The TCP/IP Reference Model
 Frame of reference used to develop the Internet's
protocols
 Consists of layers that perform functions necessary to
prepare data for transmission over a network
Description
ITE PC v4.0
Chapter 5
Protocols
HTTP, HTML,
Telnet, FTP,
SMTP, DNS
Application
Provides network services to user
applications
Transport
Provides end-to-end management of
data and divides data into segments
TCP, UDP
Internet
Provides connectivity between hosts
in the network
IP, ICMP, RIP,
ARP
Network
Access
Describes the standards that hosts
use to access the physical media
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
66
The OSI Model
 The OSI model is an industry standard framework that is
used to divide network communications into seven
layers.
 Although other models exist, most network vendors
today build their products using this framework.
 A protocol stack is a system that implements protocol
behavior using a series of layers.
Protocol stacks can be implemented either in hardware or
software, or in a combination of both.
Typically, only the lower layers are implemented in hardware,
and the higher layers are implemented in software.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
67
The OSI Model
Layer
Description
Application
7
Responsible for network services to applications
Presentation
6
Transforms data formats to provide a standard
interface for the Application layer
Session
5
Establishes, manages and terminates the
connections between the local and remote
application
Transport
4
Provides reliable transport and flow control across a
network
Network
3
Responsible for logical addressing and the domain
of routing
Data Link
2
Provides physical addressing and media access
procedures
Physical
1
Defines all the electrical and physical specifications
for devices
Remember the OSI layers with this mnemonic:
"Please Do Not Throw Sausage Pizza Away"
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
68
Compare OSI and TCP/IP Models
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
69
Configuring a NIC and a Modem
 Install the NIC and the
driver.
NIC
If necessary, download an
updated driver from the
manufacturer.
 Connect the computer to
the network.
 Also, you may need to
install a modem to connect
to the Internet.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
Modem
70
Install or Update a NIC Driver
 Manufacturers publish new driver software for NICs
May enhance the functionality of the NIC
May be needed for operating system compatibility
 Install a new driver
Disable virus protection software
Install only one driver at a time
Close all applications that are running so that they are not using
any files associated with the driver update.
Visit the manufacturer's website and download a self-extracting
executable driver file that will automatically install or update the
driver
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
71
Install or Update a NIC Driver
 Alternatively, you can click the
Update Driver button in the
toolbar of the Device
Manager.
 After updating the driver,
reboot the computer.
 If a new NIC driver does not
perform as expected after it
has been installed, the driver
can be uninstalled, or rolled
back, to the previous driver.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
72
Attach Computer to Existing Network
 Plug a network cable into the
network port on the computer.
 Plug the other end into the
network device or wall jack.
 After connecting the network
cable, look at the LEDs, or link
lights, next to the Ethernet port
on the NIC.
 If there is no activity, you may
have to replace a faulty cable,
a faulty hub port, or even a
faulty NIC to correct the
problem.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
73
Configure the NIC
 The computer will now need an IP address.
If the computer does not acquire an IP address from a DHCP
server, you will need to enter a unique IP address in the
TCP/IP properties of the NIC.
Click Start > Control Panel > Network Connections > Local
Area Connection
 Every NIC must be configured with the following
information:
The same protocol must be implemented between any two
computers that communicate on the same network.
The IP address must be unique to each device and can be
configured manually or dynamically.
The MAC address is a unique address assigned by the
manufacturer and cannot be changed.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
74
What is the Assigned IP Address?
If you do not know your IP address yet, use the ipconfig
program, to find it.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
75
Test Connectivity Using Ping
 Ping your own IP address to make sure your NIC is
working properly.
 Ping your default gateway or another computer on your
network.
 Ping a popular website.
 If you cannot ping one of these items, you may need to
begin troubleshooting.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
76
Modem Installation
 A modem is an electronic device that transfers data
between one computer and another using analog signals
over a telephone line.
A transmitting modem converts digital data to analog signals,
called modulation.
The receiving modem reconverts the analog signals back to
digital data, called demodulation.
 An internal modem plugs into an expansion slot on the
motherboard and a software driver is installed.
 External modems connect to a computer through the
serial and USB ports and also require a software driver.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
77
Dial-up Networking (DUN)
 When computers use the public telephone system to
communicate, it is called dial-up networking (DUN).
 Modems communicate with each other using audio tone
signals. DUN creates a Point-to-Point Protocol (PPP)
connection between two computers over a phone line.
 After the line connection has been established, a
"handshaking sequence" takes place between the two
modems and the computers.
 The digital signals from the computers must be
converted to an analog signal to travel across
telephone lines. They are converted back to the digital
form, 1s and 0s, by the receiving modem so that the
receiving computer can process the data.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
78
AT Commands
Function
 AT (“Attention”)
Commands - commands for modems
Attention
code
that precedes
all modem actioncommand
commands
AT modem
Most
software
uses
the Hayes-compatible
Dial the phone number, xxxxxxx, using pulse dialing
set.
AP
 Thexxxxxxx
AT command
set isnumber,
usedxxxxxxx,
to issue
dial,
Dial the phone
using
tonehang
dialing up,
ATDT
reset, and other instructions to the modem.
Answer the phone immediately
ATA
Most modem
user manuals list the AT command set.
Hang up the phone immediately
ATHO
 The
Standard
Hayes
compatible
to dial is
Reset
the modem
to its powercode
up settings
ATZ
ATDxxxxxxx
Reset modem parameters and settings to the factory
ATF
defaults
Usually no spaces in an AT string.
Break the signal, change from data mode to command mode
AT+++
The "x" signifies the number dialed.
Signifies pulse dialing
P
Seven digits for a local call and 11 digits for long-distance.
Signifies tone dialing
T
Indicates that the modem will wait
W
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
79
Other Types of Connectivity
 Phone, cable, satellite, and private telecommunications
companies provide Internet connections.
 In the 1990s, low-speed modems used the plain old
telephone system (POTS) to send and receive data.
 Today, many businesses and home users have switched
to high-speed Internet connections, which allows for
transmission of data, voice and video.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
80
Integrated Services Digital Network (ISDN)
 A standard for sending voice, video, and data over
telephone wires.
 Provides higher-quality voice and higher-speed data
transfer than traditional analog telephone service.
 Three services offered by ISDN digital connections:
Basic Rate Interface (BRI), Primary Rate Interface (PRI),
and Broadband ISDN (BISDN).
 ISDN uses two different types of communications
channels:
"B" channel is used to carry the information - data, voice, or
video.
"D" channel is usually used for controlling and signaling, but can
be used for data.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
81
ISDN Types
ITE PC v4.0
Chapter 5
Type
Description
BRI
ISDN Basic Rate Interface offers a dedicated 128
Kbps connection using two 64 Kbps B channels.
ISDN BRI also uses on 16 Kbps D channel for call
setup, control, and teardown.
PRI
ISDN Primary Rate Interface offers up to 1.544
Mbps over 23 B channels in North America and
Japan or 2.048 Mbps over 30 B channels in Europe
and Australia. ISDN PRI also uses one D channel
for call maintenance.
BISDN
Broadband ISDN manages different types of service
all at the same time. BISDN is mostly used only in
network backbones.
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
82
Digital Subscriber Line (DSL)
 An "always-on" technology; there is no need to dial up
each time to connect to the Internet.
 Uses the existing copper telephone lines to provide
high-speed data communication between end users
and telephone companies.
 Asymmetric DSL (ADSL) is currently the most
commonly used DSL technology.
Has a fast downstream speed, typically 1.5 Mbps.
Upload rate of ADSL is slower.
Not the best solution for hosting a web server or FTP server.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
83
DSL Types
ITE PC v4.0
Chapter 5
Type
Description
ADSL
Asymmetric DSL is most common. Downstream speed from
384 Kbps to 6 Mbps. Upstream speeds lower than
downstream speeds.
HDSL
High Data Rate DSL provides equal bandwidth in both
directions.
SDSL
Symmetric DSL provides the same speed, up to 3 Mbps, for
uploads and downloads
VDSL
Very High Data Rate DSL is capable of bandwidths between
13 and 52 Mbps downstream, and 16 Mbps upstream.
IDSL
ISDN DSL is DSL over ISDN lines. Uses ordinary phone
lines. Requires ISDN adapters
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
84
Power Line Communication (PLC)
 Uses power distribution wires (local electric grid) to
send and receive data.
 May be available in areas without any other service.
 Is faster than an analog modem.
 May cost less than other high-speed connections.
 Will become more common in time.
 Can be used in a home or office environment through
an electrical outlet.
 Can control lighting and appliances.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
85
Broadband Connectivity
 Broadband is a technique used to transmit and receive
multiple signals using multiple frequencies over one
cable.
 Broadband uses a wide range of frequencies that may
be further divided into channels.
 Some common broadband network connections
include:
Cable
Digital Subscriber Line (DSL)
Integrated Services Digital Network (ISDN)
Satellite
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
86
Cable Modem
 A cable modem connects your computer to the cable
company using the same coaxial cable that connects to
your cable television.
You can connect the computer directly into the cable modem.
You can connect a router, switch, hub, or multipurpose network
device so multiple computers can share the Internet connection.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
87
DSL Modem and Filter
 Voice and data signals are carried on different
frequencies on the copper telephone wires.
 A filter is used to prevent DSL signals from interfering
with phone signals. Plug the filter into a phone jack and
plug the phone into the filter.
 The DSL modem does not need a filter. A DSL modem
can connect directly to your computer,
or it can be connected to a networking device to share
the Internet connection between multiple computers.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
88
A Typical ISDN Connection
 ISDN uses multiple
channels and can
carry voice, video,
and data; therefore,
it is considered a
type of broadband.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
89
Broadband Satellite
 Uses a satellite dish for two-way
communication.
 Download speeds are typically up to
500 Kbps, while uploads are closer
to 56 Kbps.
 People in rural areas often use
satellite broadband because it is a
faster connection than dial-up and no
other broadband connection may be
available.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
90
Voice over IP (VoIP)
 Is a method used to carry telephone calls over data
networks and the Internet.
 Converts the analog signals of voices into digital
information that is transported in IP packets.
 Can also use an existing IP network to provide access
to the public switched telephone network (PSTN).
 Depends on a reliable Internet connection. When a
service interruption occurs the user cannot make phone
calls.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
91
Preventive Maintenance for Networks
 Common preventive maintenance techniques should
continually be performed for a network to operate
properly.
 Keep network rooms clean and change air filters often.
 Checking the various components of a network for wear.
 Check the condition of network cables because they are
often moved, unplugged, and kicked.
 Label the cables to save troubleshooting time later.
Refer to wiring diagrams and always follow your
company's cable labeling guidelines.
 AC power adapters should be checked regularly.
 The uninterruptible power supply (UPS) should be
tested to ensure that you have power in the case of an
outage.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
92
Troubleshooting Process
Step 1 Gather data from the
customer
Step 2 Verify the obvious issues
Step 3 Try quick solutions first
Step 4 Gather data from the
computer
Step 5 Evaluate the problem
and implement the solution
Step 6 Close with the customer
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
93
1. Gather Data from the Customer
 Customer information
Company name, contact name, address, phone number
 Computer configuration
Operating system, protection software, network environment,
connection type
 Use a work order to collect information
 Description of problem
Open-ended questions
What type of network connection is your computer using?
Closed-ended questions
Can you access the Internet?
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
94
2. Verify the Obvious Issues
Examine the most obvious causes of a problem.
 Check that the network cables are properly connected.
 If a cable is not connected properly or if a NIC is
improperly installed or configured, the LED link lights
on the NIC will not light.
 Check the wireless access point signal strength in your
network client software.
 Use the ipconfig tool to make sure that the computer
has a valid, unique IP address. Check for errors in the
subnet mask and default gateway address.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
95
3. Try Quick Solutions First
 Check that all cables are connected to the proper
locations.
 Unseat and then reconnect cables and connectors.
 Reboot the computer or network device.
 Login as a different user.
 Repair or re-enable the network connection.
 Contact the network administrator.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
96
4. Gather Data from the Computer
 Ping is used to check network connectivity. It sends a
packet to the specified address and waits for a reply.
 Nslookup is used to query Internet domain name
server. It returns a list of hosts in a domain or the
information for one host.
 Tracert is used to determine the route taken by packets
when they travel across the network. It shows where
communications between your computer and another
computer are having difficulty.
 Net View is used to display a list of computers in a
workgroup. It shows the available shared resources on
a network.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
97
5. Evaluate Problem & Implement Solution
You may need to conduct further research
 Problem solving experience
 Other technicians
 Internet search and technical websites
 News groups and online forums
 Manufacturer FAQs
 Computer and device manuals
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
98
6. Close with the Customer
When you are confident that the problem is resolved:
 Document the customer information, problem
description, and steps to resolve the issue in the work
order.
 Explain to the customer how you solved the problem .
 Let the customer verify that the problem has been
solved.
 Complete all documentation including sales orders,
time logs, and receipts.
 Complete the work order.
 Update the repair journal. You can use the notes from
the journal for future reference.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
99
Common Problems and Solutions
Problem Symptom
Possible Solution
Computer is not able to
Check DNS settings, hardware
connect to a popular website. and/or software firewall settings.
Computer has an IP address
of 169.254.x.x.
Check to make sure the DHCP server
is operational and can be pinged.
Computer is not able to
connect to the network.
Check for loose network cables.
Computer is not able to print
using the network printer.
Check user permissions and status
of network printer.
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
100
Chapter 8 Summary
 The fundamentals of networking
 The benefits of a network
 The ways to connect computers to a network
 The different aspects of troubleshooting a network
 How to analyze problems and implement simple
solutions
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
101
Additional Resources
 Telecommunication Standardization Sector of the International
Telecommunications Union (ITU-T) http://www.itu.int/ITU-T/
 Institute of Electrical and Electronics Engineers (IEEE)
http://www.ieee.org/
 International Organization for Standardization (ISO)
http://www.iso.ch/iso/
 Internet Architecture Board (IAB) http://www.iab.org/
 International Electrotechnical Commission (IEC) http://www.iec.ch/
 American National Standards Institute (ANSI) http://www.ansi.org/
 Telecommunications Industry Association (TIA)
http://www.tiaonline.org/
 Electronic Industries Alliance (EIA) http://www.eia.org/
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
102
Q and A
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
103
ITE PC v4.0
Chapter 5
© 2006 Cisco Systems, Inc. All rights reserved.
Cisco Public
104