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Chapter 6 - Networks

6.0 Networks

6.0.1 introduction >6.0.1.1 Introduction

The image on this page shows a data centre with banks of computer servers, routers, and switches on the left and right with a passageway running between them in the centre of the image. There are two people standing behind the nearest banks of servers, one on the left and one on the right. The person on the right is handing the end of an Ethernet cable, across the passageway, to the person on the left.

6.1 Principles of Networking

6.1.1 Computer Networks >6.1.1.1 Define Computer networks

The image on this page shows a desktop computer connected to a wireless router. There is also a laptop, and a wireless printer. The desktop computer and laptop are sharing data. The printer is able to receive the data sent from the desktop computer and laptop for printing.

6.1.1 Computer Networks >6.1.1.2 Features and Benefits

The image on this page shows 3 workstations connected to a server. The server is connected to printers, scanners, modems, applications and files. Network computers share resources.

6.1.1 Computer Networks >6.1.1.3: Activity - Advantages and Disadvantages of Networking

The figure on this page is an interactive activity that allows the learner to classify characteristics of networks as either a PRO or a CON of networking. CON has two characteristics and PRO has three characteristics.

The available characteristics are:

• Networks have to be administered
• Centralised backup of data
• Networks allow group access to documents
• Peripherals can be shared
• Can be difficult to troubleshoot

The figure also has the following 2 buttons:

• Check
• Reset

6.2 Identifying Networks

6.2.1 Types of Networks >6.2.1.1 LANs

The figure on this page shows a local area network (LAN) consisting of three workstations, a server, and an IP phone, all connected to a central switch.

6.2.1 Types of Networks >6.2.1.2 WLANs

The figure on this page shows a wireless local area network (WLAN) that has three desktop computers connected to a central wireless router.

6.2.1 Types of Networks >6.2.1.3 PANs

The image on this page shows a person with a personal area network (PAN) that uses Bluetooth technology and consists of a smart phone, wireless laptop, a wireless printer and a wireless speaker.

6.2.1 Types of Networks >6.2.1.4 MANs

The figure on this page shows a group of buildings that are all interconnected to form a metropolitan area network (MAN). The image also shows that there are LANS in three of the buildings and that one of the buildings in the MAN is connected to another building that is not part of the MAN forming a WAN.

6.2.1 Types of Networks >6.2.1.5 WANs

The figure on this page shows two LANs connected over a serial connection forming a Wide Area Network (WAN)

6.2.1 Types of Networks >6.2.1.6 Peer-to-Peer Networks

The figure on this page shows three computers connected to a switch creating a peer to peer network.

6.2.1 Types of Networks >6.2.1.7 Client/Server Networks

The figure on this page shows a server that is an Email server, Web server and File Server connected to the following four client computers:

• Web browser, File Access Client
• Web Browser, Email Client
• File Access Client
• Web Browser, Email Client, File Access Client

6.2.1 Types of Networks >6.2.1.8: Activity - Matching Network Types

The figure on hsi page is an interactive activity that allows the learner to match network descriptions to the correct network type.

The network types are:

• LAN
• WAN
• WLAN
• PAN
• MAN
• Peer-to-Peer
• Client/Server

The network descriptions are:

• This type of network uses many technologies to connect distant networks.
• This type of network can span a city.
• This type of network has centralised administration.
• This type of network has no centralised administration.
• This type of network uses access points and wireless NICs for connectivity.
• This type of network uses cable connections in a single administrative group.
• This type of network connects devices within the range of an individual person.

The figure also has the following 2 buttons:

• Check
• Reset

6.3 Basic Networking Concepts and Technologies

6.3.1 Data Flow >6.3.1.1 Bandwidth

The image on this page shows the following three statements about networks and related images:

1. Bandwidth is like the number of lanes.

• The images are:
  • A single lane road
  • A double lane road
  • A six lane highway

2. Network devices are like ramps, traffic signals, signs, and maps.

• The images are:
  • A highway on ramps
  • A traffic Signal
  • A stop sign and a curve right sign
  • A map

3. Travelling data is like travelling vehicles.

• The images are:
  • A car
  • An off-road vehicle

6.3.1 Data Flow >6.3.1.2 Data Transmission

The 2 figures on this page show the difference between Half Duplex and Full Duplex. Both the figures show two computers connected over a network.

Half-Duplex:

• PC1 has a callout saying, "I can send and receive, but not at the same time.".
• PC1 has a callout saying, "I can send and receive, but not at the same time.".

Full-Duplex:

• PC1 and PC2 have a callout saying, "We can send and receive at the same time.".

6.3.2 Networked Equipment Addressing >6.3.2.1 IP Addressing

The figure on this page shows a computer user sitting at a computer which is connected to a wireless router. The router is connected three servers on the internet. The following IP addresses for the computer and the servers are displayed:

Device	IP Address
Computer	192.168.200.8
www.cisco.com server	192.0.2.100
Business A server	198.51.100.5
Business B server	203.113.0.50

6.3.2 Networked Equipment Addressing >6.3.2.2 IPv4

The figure on this page shows the following tables listing the IPv4 address classes:

Class A	Network	Host
Octet	1	2	3	4
Default subnet Mask	255	0	0	0
IP Address Range	1.0.0.0 to 126.255.255.255
Hosts Per Network	2^24-2=16,777,214

Class B	Network		Host
Octet	1	2	3	4
Default subnet Mask	255	255	0	0
IP Address Range	128.0.0.0 to 191.255.255.255
Hosts Per Network	2^16-2=65,534

Class C	Network			Host
Octet	1	2	3	4
Default subnet Mask	255	255	255	0
IP Address Range	192.0.0.0 to 223.255.255.255
Hosts Per Network	2^8-2=254

Class D addresses are used for multicast groups, such as webcasts or streaming videos to a select group. Class E addresses are used for research use only.

6.3.2 Networked Equipment Addressing >6.3.2.3 IPv6

Figure 1 on this page shows the following three-part hierarchy of IPv6 addreses.

Address are 128 bit

3ffe:6a88:85a3:08d3:1319:8a2e:0370:7344

Addresses are expressed as 8 hexadecimal values, separated by colons.
Each value is 16 bits long. 8 x 16 = 128

	Address Hierarchy
!IPv6 Address	Global prefix	Subnet ID	Interface ID
3ffe:6a88:85a3:08d3:1319:8a2e:0370:7344	3ffe:6a88:85a3	:08d3:	1319:8a2e:0370:7344

The figure also shows the IPv6 address with the Subnet ID, '08d3' highlighted.

Figure 2 on this page shows the following table with an example of how the IPv6 rules for abbreviating addresses are applied:

Rules for Abbreviating IPv6 Address
Address	2001	:	0db8	:	0000	:	0000	:	0000	:	0000	:	1428	:	57ab
After Rule 1	2001	:	0db8	:	0	:	0	:	0	:	0	:	1428	:	57ab
After Rule 2	2001	:	0db8	:								:	1428	:	57ab

Below are the text representation of these addresses
Address	2001:0db8:0000:0000:0000:0000:1428:57ab
After Rule 1	2001:0db8:0:0:0:0:1428:57ab
After Rule 2	2001:0db8::1428:57ab

6.3.2 Networked Equipment Addressing >6.3.2.4 Static Addressing

Image 1 on this page shows the General control tab in the Windows XP Internet Protocol version 4 (TCP/IPv4) Properties dialog box where the user is able to configure the IP address, Subnet Mask, Default gateway as well as Preferred DNS server and Alternative DNS Server.

Image 2 on this page shows the Windows XP Network Connection Details window. This displays information such as: The name and model of the hardware that is being used to make the link happen between the computer and the network, MAC address (Physical address), IPv4 address, Subnet Mask, Default Gateway, DNS server, DHCP server, Lease obtained and lease expires, DHCP enabled and other information.

6.3.2 Networked Equipment Addressing >6.3.2.5 DHCP Addressing

Image 1 on this page shows 2 versions of the General tab in the Windows XP Internet Protocol version 4 (TCP/IPv4) Properties dialog box. The first version has the Obtain an IP address automatically option selected. It also has the Use the following DNS server addresses option selected. The second version has the Obtain an IP address automatically option selected. It also has the Obtain DNS server address automatically option selected. See page notes for full description.

Image 2 on this page shows the General tab in the Windows XP Internet Protocol version 4 (TCP/IPv4) Properties dialog box highlighting the Obtain DNS server address automatically option.

Image 3 on this page shows the Alternative Configuration tab in the Windows XP Internet Protocol version 4 (TCP/IPv4) Properties dialog box highlighting the User Configure option. See page notes for full description.

6.3.2 Networked Equipment Addressing >6.3.2.6 ICMP

The image on this page shows the Windows XP Command Prompt executing the following ping command:

C:\>ping cisco.com

Pinging cisco.com [198.133.219.25] with 32 bytes of data:

Request timed out.
Request timed out.
Request timed out.
Request timed out.
@@

Ping statistics for 198.133.219.25:
  Packet: Sent = 4, Received = 0, Lost = 4 (100% loss),

C:\>

END OF COMMAND PROMPT OUTPUT

6.3.2 Networked Equipment Addressing >6.3.2.7: Lab - Configure a NIC to Use DHCP in Windows 7

See IT Essentials 5.0 Labs and Worksheets Accessible Files

6.3.2 Networked Equipment Addressing >6.3.2.8: Lab - Configure a NIC to Use DHCP in Windows Vista

See IT Essentials 5.0 Labs and Worksheets Accessible Files

6.3.2 Networked Equipment Addressing >6.3.2.9: Lab - Configure a NIC to Use DHCP in Windows XP

See IT Essentials 5.0 Labs and Worksheets Accessible Files

6.3.2 Networked Equipment Addressing >6.3.2.10: Packet Tracer - Adding Computers to an Existing Network

This task cannot be completed as it requires Packet Tracer, which is inaccessible.

Common Ports and Protocols >6.3.3.1 TCP and UDP

The figure on this page shows the following table listing the advantages and applications for TCP and UDP:

TCP	UDP
Advantages: Error Detection - TCP retransmits lost packets, drops duplicate packets, and guarantees that data is transmitted in the proper order. Reliable transport Protocol - TCP tracks data to guarantee it is delivered to the destination.	Advantages: Lower Overhead - Uses less bandwidth than TCP. Connectionless - There is no requirement that the recipient is available and ready to receive data and there is no requirement of acknowledgement of receipt.
Application: Email Web Browser	valign=top:) Applications: Simple File Transfer - Sends data without security and does not require acknowledgement of receipt. Network file system - A system for accessing files over a network that is similar to the way files are accessed locally.

Common Ports and Protocols >6.3.3.2 Activity - TCP vs. UDP

The figure on this page is an interactive activity that allows the learner to match the protocol with a list of advantages. Each protocol can have six advantages.

The protocols are:

• TCP
• UDP

The advantages are:

• Email
• Error Detection
• Reliable Delivery of Data
• Simple File Transfer
• Lower Overhead
• Connectionless
• Network File Systems
• Unreliable Delivery of Data
• Web Browser

The figure also has a Reset button.

Common Ports and Protocols >6.3.3.3 TCP and UDP Protocols and Ports

The figure on this page shows the following table listing the common network protocols and ports:

Protocol	Port	Description
TCP/IP	NA	A suite of protocols used to transport data on the internet
NetBEUI/ NetBIOS	137, 139, 150	A small, fast protocol designed for a workgroup network that requires no connection to the internet
HTTP	80	A communication protocol that establishes a request/response connection on the internet
HTTPS	443	Uses Authentication and encryption to secure data as it travels between the client and web server
FTP	20/21	Provide services for file transfer and manipulation
SSH	22	Securely connects to a remote network device
Telnet	23	Connects to a remote network device
POP3	110	Downloads email messages from an email server
IMAP	143	Downloads email messages from an email server
SMTP	25	Sends email in a TCP/IP network
LDAP	389	Accesses information directories
SNMP	161	Manages and monitors devices on a network
SMB	445	Provides shared access to files, printers, and communication between points on a network
SFTP	115	Provides a secure file transfer service
DNS	53	Resolves host names to IP addresses
RDP	3389	Used to provide access to a remote computer

Common Ports and Protocols >6.3.3.4: Worksheet - Protocol Definitions and Default Ports

In this worksheet, the learner will write the name of the protocol and the default port(s) for each protocol definition in the table. See IT Essentials 5.0 Labs and Worksheets Accessible Files

6.4 Physical Components of a Network

6.4.1 Network Devices >6.4.1.1 Modems

The image on this page shows the following three different types of modems.:

• Cable Modem
• DSL modem
• Internal PCI Modem Adapter

6.4.1 Network Devices >6.4.1.2 Hubs, Bridges, and Switches

Figure 1 on this page shows an image of the front and back of a hub. The figure also shows a diagram of four computers, a server, and a printer connected to a central hub.

Figure 2 on this page shows an image of the top and back of a switch. The figure also shows a diagram of a computer, a server, and an IP phone connected to a central switch.

6.4.1 Network Devices >6.4.1.3 Routers and Wireless Access Points

Figure 1 on this page shows an image of the top and back of a DSL modem. The figure also shows a diagram of a DSL modem connecting a home to a telephone line and a cable modem connecting a home to a coaxial cable.

Figure 2 on this page shows an image of a wireless access point. The figure also shows a diagram of a wired local area network consisting of three computers, a server, and a printer connected to a wireless access point. The wireless access point is broadcasting Internet signal to three laptops.

Figure 3 on this page shows an image of a Cisco multipurpose device that is a home gateway, a wireless access point and a switch.

6.4.1 Network Devices >6.4.1.4 NAS

The image on this page shows a Network-attached storage (NAS) device which allows a user to store videos, music, pictures and files and to be able to access the files anywhere in the world with an internet connection.

6.4.1 Network Devices >6.4.1.5 VoIP Phones

The image on this page shows arious IP phones from Cisco and Linksys which look like standard ordinary telephones.

6.4.1 Network Devices >6.4.1.6 Hardware Firewalls

Figure shows the internal firewall feature of an integrated router protecting two hosts on an internal network.

The figure on this page shows how a hardware firewall works.

An internal network consisting of hosts H1 and H2and a web server are connected to an integrated router. The integrated router consists of an internal router, an internal firewall, and an ethernet switch.

An external network, H3 wants to log in to the internal network. the H3 network traffic is directed by the internal router which then sends the H3 network traffic to the internal firewall. If the network traffic is allowed to go through the internal firewall the H3 network traffic is then sent to the Ethernet switch which is connected to all of the wired computers in the internal network giving the H3 access to the internal network. If the H3 network traffic was not allowed to go through the network then the traffic would be blocked and prevented from entering the internal network.

6.4.1 Network Devices >6.4.1.7 Internet Appliances

The image on this page shows the Cisco web TV appliance running.

6.4.1 Network Devices >6.4.1.8 Purchasing Authentic Networking Devices

The image on this page shows two Cisco network devices side by side that look identical. One is authentic and the other is a counterfeit product.

The description given for this figure is, "The cosmetic differences between an authentic product and a counterfeit can be extremely subtle or non existent.".

6.4.2 Cables and Connectors >6.4.2.1 Considerations for Cabling a Network

The images on this page show the following three different types of network cables:

• Twisted Pair
• Coaxial Cable
• Fibre Optic

6.4.2 Cables and Connectors >6.4.2.2 Coaxial Cables

Image 1 on this page shows a coaxial cable with the different layers exposed.

Image 2 on this page shows the following different layers of a coaxial cable:

• Outer Jacket
• Braided Copper Shielding
• Plastic Insulation
• Copper Conductor

Image 3 on this page shows the following two types of coaxial connectors. See page notes for full description:

• BNC
• F type

6.4.2 Cables and Connectors >6.4.2.3 Twisted-Pair Cables

Figure 1 on this page is an image showing the different pairs of copper wires in a twisted-pair cable encased in colour-coded insulation and twisted together.

(Figure 2 on this page shows the following table of Twisted-Pair Cable Features.:

	Speed	Features
Cat 3 UTP	10 Mb/s at 16MHz	Suitable for Ethernet LAN. Most often used for phone lines.
Cat 5 UTP	100 Mb/s at 100MHz	Manufactured with higher standard than Cat 3 to allow for higher data transfer rates.
Cat 5e UTP	1000 Mb/s at 100MHz	Manufactured with higher standard than Cat 5 to allow for higher data transfer rates More twists per foot than Cat 5 to better prevent EMI and RFI from outside sources
Cat 6 UTP	1000 Mb/s at 250MHz	Manufactured with higher standard than Cat 5e. More twists per foot than Cat 5e to better prevent EMI and RFI from outside sources. Cat 6a has better insulation and performance than cat 6. May have plastic divider to separate pairs of wires inside the cable to better prevent EMI and RFI. Good choice for customers using applications that require large amounts of bandwidth, such as video conferencing or gaming. ScTP (Screened Twisted Pair) is very expansive and not as flexible as UTP.
Cat 6a UTP	1000 Mb/s at 500MHz
Cat 7 ScTP	10 GB/s at 600MHz

Figure 3 on this page shows an image of a Cat 3 cable with a 6 pin RJ11 connector and a Cat 3 cable with 8 pin RJ 45 connector.

6.4.2 Cables and Connectors >6.4.2.4: Lab - Building Straight-Through and Crossover UTP Cables

 See IT Essentials 5.0 Labs and Worksheets Accessible Files

6.4.2 Cables and Connectors >6.4.2.5: Packet tracer - Cabling a Simple Network

This task cannot be completed as it requires Packet Tracer, which is inaccessible.

6.4.2 Cables and Connectors >6.4.2.6 Fibre-Optic Cables

The figure on this page shows a perspective view and a front view of a fibre-optic cable with the following different layers exposed:

• Jacket (Typically PVC)
• Strengthening Material (Aramid Yarn)
• Buffer
• Cladding
• Core

The figure also shows an image of three different fibre-optic cables with different connectors and four different sockets. See page notes for full description.

6.5 Network Topologies

6.5.1 Topologies >6.5.1.1 Logical and Physical Topologies

The figure on this page is an interactive activity that allows the learner to view a number of different physical topologies. The figure consists of six buttons with the names of different topologies. As each button is selected the corresponding topology is displayed. See page notes for full description.

The topologies are:

• Bus Topology
• Ring Topology
• Star Topology
• Extended Star
• Mesh Topology
• Hybrid Topology

6.5.1 Topologies >6.5.1.2: Packet Tracer - Physical Topologies

This task cannot be completed as it requires Packet Tracer, which is inaccessible.

6.5.1 Topologies >6.5.1.3 Determining the Network Topology

The figure on this page shows the network topology of a school. The network consists of the five following separate buildings:

Building	Devices
Admin Office	2 PCs Printer Admin Switch Ethernet Switch
Server Room	File Server Mail Server Web Server Switch Router
Classroom 1	2 PCs Printer Classroom Switch
Classroom 2	3 PCs Classroom Switch
Classroom 3	3 PCs Classroom Switch

• The Admin Switch is connected to the Switch in the Server Room.
• The three Classroom Switches are connected to the Ethernet Switch in the Admin Office
• The Ethernet Switch is connected to the Router in the Server Room
• The Router is connected to the Internet

6.6 Ethernet Standards

6.6.1 Cabled and Wireless >6.6.1.1 Standards Organisations

The figure on this page shows the following table listing the various standards organisations for setting networking standards:

Standards Organisation	Description
ITU-T	The international Telecommunications Unions, Telecommunication Standardization Sector – The United Nations specialized agency for information and communication technologies (ICTs).
IEEE]	Institute of Electrical and Electronics Engineering – Develops standards for computer and electronic industry. For example the IEEE 802 standard for local area networks.
ISO	International Organisation for standardization- Defines computer standards. For example the Open System interconnection (OSI) model.
IAB	Internet Architecture Board- A committee that oversee the technical and engineering development of the internet.
IEC	International Electro technical Commission – Is the global organisation that prepares and publishes international standards for all electrical, electronic, and related technologies.
ANSI	American National Standards Institute – Facilitates the development of standards by establishing consensus processes among qualified groups.
TIA/EIA	Telecommunications Industry Association and Electronic Industries Alliance – Develop and publish standards covering structured voice and data wiring for LANs.

6.6.1 Cabled and Wireless >6.6.1.2 IEEE 802.3

The figure on this page is an interactive activity that illustrates to the learner collisions in a hub based network.

The network consists of hosts H1 to H8 connected to a central hub. When data is sent by two random hosts each will send a data packet to the hub at the same time. When these two packets reach the hub at the same time they collide, therefore causing data transmission errors. See page notes for full description.

6.6.1 Cabled and Wireless >6.6.1.3 Ethernet Technologies

The figure on this page shows the following table listing the following different IEEE 802.3 ethernet standards:

Ethernet Standards	Media	Transfer RatesAC
10BASE-T	Category 3	Transfers data at a rate of 10MB/s
100BASE-TX	Category 5	At 100 MB/s, transfer rates of 100BASE-TX are ten times that of 10BASE-T.
1000BASE-T	Category 5e,6	The 1000BASE-T architecture supports data transfer rates of 1 Gb/s
10GBASE-T	Category 6a,7	The 10GBASE-T architecture supports data transfer rates of 10 Gb/s

6.6.1 Cabled and Wireless >6.6.1.4 IEEE802.11

The figure on this page shows the following table listing the following different IEEE 802.11 wireless ethernet standards:

Standard	Bandwidth	Frequency	Maximum Range	Client Interoperability
IEE 802.11a	Up to 54 Mb/s	5 GHz band	45.7 m (150 ft)	Not interoperability with 802.11b, 802.11g,802.11n
IEE 802.11b	Up to 11 Mb/s	2.4 GHz band	91 m (300 ft)	interoperability with 802.11g
IEE 802.11g	Up to 54 Mb/s	2.4 GHz band	91 m (300 ft)	interoperability with 802.11b
IEE 802.11n	Up to 600 Mb/s	2.4 GHz or 5 GHz band	250 m (984 ft)	interoperability with 802.11g, 802.11a,802.11b

6.7 OSI and TCP/IP Data Models

6.7.1 Reference Models >6.7.1.1 TCP/IP

The figure on this page shows the following table listing the TCP/IP layers:

TCP/IP Layer	Description
Application	Where high level protocols such as SMTP and FTP operate
Transport	Specifies which application requested or is receiving data through specific ports
Internet	Where IP addressing and routing take place
Network Access	Where MAC addressing and physical components of the network exist

6.7.1 Reference Models >6.7.1.2 OSI

The figure on this page shows the following table listing the OSI layers:

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

6.7.1 Reference Models >6.7.1.3 Comparing the OSI and TCP/IP Models

The figure on this page compares the TCP/IP and OSI models.

OSI Reference Model	TCP/IP Model
Application	Application
Presentation
Session
Transport	Transport
Network	Internet
Data link	Network Access
Physical

• The Application, Presentation, and Session layers of the OSI model align with the Application layer of the TCP/IP model
• The Transport layer of the OSI model align with the Transport layer of the TCP/IP model
• The Network layer of the OSI model align with the Internet layer of the TCP/IP model
• The Data Link and Physical layers of the OSI model align with the Network Access layer of the TCP/IP model

6.7.1 Reference Models >6.7.1.4 Activity - Match the OSI Model to the TCP/IP Model

The figure on this page is an interactive activity that allows the learner to match the OSI Model layers to the TCP/IP Model layers.

The TCP/IP Model layers are:

• Internet
• Application
• Network Access
• Transport

The OSI Model layers are:

• Application
• Transport
• Network
• Presentation
• Data Link
• Session
• Physical

The figure also has the following 2 buttons:

• Check
• Reset

6.8 Computer to Network Connection

6.8.1 Network Installation Steps >6.8.1.1 Network Installation Completion List

The figure on this page shows a floor plan diagram of an office space with 3 new desktop computers as well as the new equipment rack and patch panel. The diagram also shows the basic wiring layout.

6.8.2 Network Cards >6.8.2.1 Selecting a NIC

The figure on this page shows three images of the following different network interface cards:

• Ethernet PCI Express interface card
• Wireless PCI Express interface card
• wireless USB

6.8.2 Network Cards >6.8.2.2: Worksheet - Internet Search for NIC Devices

See IT Essentials 5.0 Labs and Worksheets Accessible Files

6.8.2 Network Cards >6.8.2.3 Installing and Updating a NIC

The image on this page shows Driver tab of the Broadcom NetXtreme Gigabit Ethernet Properties window with the Roll Back Driver button highlighted.

6.8.2 Network Cards >6.8.2.4: Lab - Install a Wireless NIC in Windows 7

See IT Essentials 5.0 Labs and Worksheets Accessible Files

6.8.2 Network Cards >6.8.2.6: Lab - Install a Wireless NIC in Windows Vista

See IT Essentials 5.0 Labs and Worksheets Accessible Files

6.8.2 Network Cards >6.8.2.6: Lab - Install a Wireless NIC in Windows XP

See IT Essentials 5.0 Labs and Worksheets Accessible Files

6.8.2 Network Cards >6.8.2.7 Configuring a NIC

Image 1 on this page shows the Local Area Connection Properties window listing the following available protocols that the device uses:

• Client for Microsoft Network
• QoS Packet Scheduler
• File and Printer Sharing for Microsoft Networks
• Internet Protocol Version 6 (TCP/IPv6)
• Internet Protocol Version 4 (TCP/IPv4)
• Link Layer Topology Discovery Mapper I/O Driver
• Link Layer Topology Discovery Responder

Image 2 on this page shows the Alternate Configuration tab of the Internet Protocol Version 4 (TCP/IPv4) Properties window. If the computer is used on more than one network the user can enter the following alternate IP settings:

• IP address
• Subnet mask
• Default gateway
• Preferred DNS server
• Alternate DNS server
• Preferred WINS server
• Alternate WINS server

6.8.2 Network Cards >6.8.2.8 Advanced NIC Settings

Image 1 on this page shows the Advanced tab of the Broadcom Gigabit Ethernet Properties window. Two text list boxes are displayed, Property and Value. The Speed and Duplex property is selected as well as the value of Auto.

Image 2 on this page shows the Advanced tab of the Atheros Fast Ethernet Controller Properties window. Two text list boxes are displayed, Property and Value. The Wake Up Capabilities property is selected as well as the value of Magic Packet.

Image 3 on this page shows the Select Network Service window with QoS packet Scheduler installed.

6.8.2 Network Cards >6.8.2.9: Packet Tracer - Install a Wireless NIC

This task cannot be completed as it requires Packet Tracer, which is inaccessible.

6.8.3 Wireless and Wired Router Configurations >6.8.3.1 Connecting to the Router

The image on this page shows an ethernet cable about to be plugged into a router. The three LEDs next to the ethernet port are circled. See page notes for full description.

6.8.3 Wireless and Wired Router Configurations >6.8.3.2 Setting the Network Location

Image 1 on this page shows the Set Network Location window. See page notes for full description.

Image 2 on this page shows the Advanced sharing settings window of the Network and Sharing Center utility. The available settings are as follows:

• Network Discovery
• File and Printer Sharing
• Public Folder Sharing
• Media Streaming
• File Sharing Connections
• Password Protected Sharing
• Home Group Connections

6.8.3 Wireless and Wired Router Configurations >6.8.3.3 Logging in to the Router

The image on this page shows the Windows Security window where the user can enter the username and password. There is also a checkbox box to allow Windows to Remember my credentials.

6.8.3 Wireless and Wired Router Configurations >6.8.3.4 Basic Network Setup

The image on this page shows the Cisco E2500 Router Setup Page open in Internet Explorer. Here the user can set options including the following:

• Language
• Host Name
• Domain Name
• IP Address
• Subnet Mask
• Router Name
• DCHP Server
• Static IP Address
• Maximum number of users

6.8.3 Wireless and Wired Router Configurations >6.8.3.5: Lab - Connect to a Router for the First Time

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6.8.3 Wireless and Wired Router Configurations >6.8.3.6: Packet Tracer - Connect to Wireless Router and Configure Basic Settings

This task cannot be completed as it requires Packet Tracer, which is inaccessible.

6.8.3 Wireless and Wired Router Configurations >6.8.3.7 Basic Wireless Settings

The image on this page shows the E2500 Wireless Setup Screen open in Internet Explorer. Here the user can set the following options for both 5 GHZ and 2.4 GHz:

• Network Model
• Network Name (SSID)
• Channel Width
• Channel
• SSID Broadcast

6.8.3 Wireless and Wired Router Configurations >6.8.3.8: Lab - Configure Wireless Router in Windows 7

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6.8.3 Wireless and Wired Router Configurations >6.8.3.9: Lab - Configure Wireless Router in Windows Vista

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6.8.3 Wireless and Wired Router Configurations >6.8.3.10: Lab - Configure Wireless Router in Windows XP

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6.8.3 Wireless and Wired Router Configurations >6.8.3.11: Packet Tracer - Connecting Wireless PCs to a Linksys WRT300N

This task cannot be completed as it requires Packet Tracer, which is inaccessible.

6.8.3 Wireless and Wired Router Configurations >6.8.3.12 Testing Connectivity with the Windows GUI

The image on this page shows the Wireless Network Connection Status window displaying the following information:

• IPv4 Connectivity
• IPv6 Connectivity
• Media State
• SSID
• Duration
• Speed
• Signal Quality
• Activity, bytes sent and received

6.8.3 Wireless and Wired Router Configurations >6.8.3.13 Testing Connectivity with the Windows CLI

Figure 1 on this page shows the following table listing the different Ipconfig Command Options:

Ipconfig Command\Options	Purpose
/all	Displays full configuration information of all network adapters
/release	Releases the IP address of a network adapter
/renew	Renews the IP address of a network adapter
/flushdns	Empties the cache that stores DNS information
/registerdns	Refreshes the DHCP lease and re-registers the adapter with the DNS
/displaydns	Shows DNS information in the cache

Figure 2 on this page shows the following table listing the different Ping Command Options:

Ping Command Options	Purpose
-t	Ping the specified host until stopped
-a	Resolve the address to a hostname
-n count	Number of echo requests to send
-l size	Send the buffer size
-f	Set the Don't Fragment flag in the packet
-i TTL	Time to Live
-v TOS	Type Of Service
-r count	Record the route for count hops
-s count	Timestamp for count hops
-j host-list	Loose source route along host-list
-K host-list	Strict source route along host-list
-w time out	Timeout in milliseconds to wait for each reply

Figure 3 on this page shows the following table listing the Net Commands:

Net commands	Purpose
Net/? or net help	Displays the net commands
nbtstat	Displays protocol statistics and current TCP/IP connections using NetBIOS over TCO/IP(NBT)
netstat	Displays active TCP connections
net accounts	Updates the user accounts database and modifies password and logon requirements.
net computer	Adds or deletes computers
net config [workstation|server]	Displays configuration information
net continue	Continues a service that has been suspended by net pause
net file	Displays the names of all open shared files on a server
net group	Adds, displays, or modifies global groups
net help [command]	Displays information about specific net commands
net helpmsg	Provides error and problem solving information
net localgroup	Adds, displays, or modifies local groups
net name	Adds or deletes a messaging name
net pause	Pauses services that are currently running
net print	Displays print queue or print job information, or controls a specified print job
net send	Sends messages
net session	Displays or Disconnects sessions between computers
net share	Displays or manages shared printers or directories
net start	Displays started services
net statistics [workstation|server ]	Displays workstation and server statistics
net stop [service]	Stops specified network service
net time	Displays or synchronizes network time
net use	Displays or manages remote connections
net user	Creates, modifies, or lists user accounts
Net view	Displays network resources or computers

6.8.3 Wireless and Wired Router Configurations >6.8.3.14: Lab - Test the Wireless NIC in Windows 7

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6.8.3 Wireless and Wired Router Configurations >6.8.3.15: Lab - Test the Wireless NIC in Windows Vista

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6.8.3 Wireless and Wired Router Configurations >6.8.3.16: Lab - Test the Wireless NIC in Windows XP

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6.8.3 Wireless and Wired Router Configurations >6.8.3.17: Packet Tracer - Test a Wireless Connection

This task cannot be completed as it requires Packet Tracer, which is inaccessible.

6.8.4 OS Configurations >6.8.4.1 Domain and Workgroup

The image on this page shows the windows 7 System information window with the following information displayed:

• Computer Name: Student_01
• Full Computer Name: Student_01
• Workgroup: WORKGROUP

6.8.4 OS Configurations >6.8.4.2 Connecting to a Workgroup or a Domain

Image 1 on this page shows the Windows 7 Computer Name /Domain Changes window where the user can enter the Computer name and the Domain or Workgroup name.

Image 2 on this page shows the Join a Domain or Workgroup window with the following options:

• This computer is part of a business network; I use it to connect to other computers at work
• This is a home computer; it's not part of a business network

6.8.4 OS Configurations >6.8.4.3 Windows 7 Homegroup

Image 1 on this page shows the Network and Sharing Center window which has three sections.

The first section is a network map showing the computer connected to the network which is connected to the Internet.

The second section, View your Active Networks displays your network name, access type and connection strength represented by bars.

The third section, Change your Network Settings has the following options:

• Set up a new connection or network
• Connect to a network
• Choose home group and sharing options
• Troubleshoot problems.

Image 2 on this page shows the HomeGroup window which displays the following three links when a homegroup can be created:

• Tell me more about homegroups
• Change advanced sharing settings
• Start the HomeGroup troubleshooter

The window also displays a Create a Homegroup button

Image 3 on this page shows the HomeGroup window which is displayed when the user can join a homegroup. The wondow lists the same three links as when a homegroup can be created but the Create a homegroup button is replaced with a Join now button.

6.8.4 OS Configurations >6.8.4.4 Sharing Resources in Windows Vista

The image on this page shows the Windows Vista Network and Sharing Centre utility listing the following settings:

• Network discovery
• File sharing
• Public folder sharing
• Printer sharing
• Password protected sharing
• Media sharing

6.8.4 OS Configurations >6.8.4.5 Sharing Resources in Windows XP

The image ion this page shows the Windows XP Network Setup Wizard where the user can:

• Share an Internet connection
• Set up Windows Firewall
• Share files and folders
• Share a printer

6.8.4 OS Configurations >6.8.4.6 Network Shares and Mapping Drives

Image 1 on this page shows the Permissions window of a shared folder.. The window has two sections.

The first section is Group or usernames which lists all of the current groups and users that have access to the folder. Below this section are the following two buttons:

• Adding
• Remove

The second section lists Permissions for groups and users. Each type of permission can be either allowed or denied. The types of permissions are:

• Full Control
• Change
• Read

Image 2 on this page shows the Map Network Drive utility where the user can specify the drive letter for the connection and the folder that the user wants to connect to. The following two checkboxes are also displayed:

• Reconnect at logon
• Connect using different credentials

6.8.4 OS Configurations >6.8.4.7: Lab - Share a Folder create a Homegroup and Map a Network Drive in Windows 7

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6.8.4 OS Configurations >6.8.4.8: Lab - Share a Folder create a Homegroup and Map a Network Drive in Windows Vista

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6.8.4 OS Configurations >6.8.4.9: Lab - Share a Folder create a Homegroup and Map a Network Drive in Windows XP

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6.8.4 OS Configurations >6.8.4.10 VPN

The image on this page shows the Connect VPN Connection Utility. The user can join a Virtual Private Network by entering the user name, password, and domain.

6.9 Select an ISP Connection Type

6.9.1 Connection Technologies >6.9.1.1 Brief History of Connection Technologies

The image on this page shows a satellite dish, a broadband modem and a broadband splitter device.

6.9.1 Connection Technologies >6.9.1.2 DSL and ADSL

The figure on this page shows a home computer connected to a DSL modem which is connected to the ISP using a twisted pair Ethernet cable.

6.9.1 Connection Technologies >6.9.1.3 Line of Sight Wireless Internet Service

The figure on this page shows a wireless transmission tower which has a direct line of sight through satellite dishes to a hone's receiver. This allows a wireless network to be created inside the home that connects all of the devices in the home to each other and to the Internet.

6.9.1 Connection Technologies >6.9.1.4 WiMAX

The figure on this page shows an ISP network sending the signal through a cable to a WiMax transmitter which then sends the signal to another WiMax transmitter which broadcasts the signal to a home which is in line of sight, therefore providing Internet access.

6.9.1 Connection Technologies >6.9.1.5 Other Broadband technologies

The figure on this page shows an ISP satellite service provider sending a signal to a satellite which relays the signal to a satellite modem connected to a laptop.

6.9.1 Connection Technologies >6.9.1.6: Worksheet - Answer Broadband Questions

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6.9.1 Connection Technologies >6.9.1.7 Selecting an ISP for the Customer

The figure on this page shows the following table listing the various types of Internet connections offerred by ISPs:

Type	Advantages	Disadvantages	Speed
POTS	Widely available	Very slow speeds, Cannot receive phone calls when connected	MAX 56 kbps
ISDN	Higher Speeds than POTS	Still much slower than other broadband technologies	BRI - up to 128 kbps PRI - up to 2.048 Mb/s
DSL	Low cost	Distance from CO impacts speeds	24 - kbps - 100 Mb/s
Cable	Very high speed	Slow upload speeds	27 kbps - 16- Mb/s
Satellite	Available where DSL and cable are not	More expensive than other broadband technologies, and it is susceptible to weather conditions	9 kbps - 24 Mb/s
Cellular	Available to mobile users	Not accessible every where	20 kbps and up depending on the technology used

6.9.1 Connection Technologies >6.9.1.8: Worksheet - ISP Connection Types

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6.10 Common Preventative Maintenance Techniques Used for Networks

6.10.1 Network Maintenance >6.10.1.1

The image on this page shows two IT technicians trying to identify issues within the server rack with one of the technicians holding a laptop computer.

6.11 Basic Troubleshooting Process for Networks

6.11.1 Applying the Troubleshooting Process to Networks >6.11.1.1 Identify the Problem

The figure on this page shows the following table listing the first step in troubleshooting network problems:

Step 1: Identify the Problem
Open-Ended Questions	What problems are you experiencing with your computer or network device? What software has been installed on your computer recently? What were you doing when the problem was identified? What error messages have you received? What type of network connection is the computer using?
Close-ended Questions	Has anyone else used your computer recently? Can you see any shared files or printers? Have you changed your password recently? Can you access the internet? Are you currently logged into the network?

6.11.1 Applying the Troubleshooting Process to Networks >6.11.1.2 Establish a Theory of Probable Cause

The figure on this page shows the following table listing the second step in troubleshooting network problems:

Step 2: Establish a Theory of Probable Cause
Common causes of network problems	Loose cable connections Improperly installed NIC ISP is down Low wireless signal strength Invalid IP address

6.11.1 Applying the Troubleshooting Process to Networks >6.11.1.3 Test the Theory to Determine Cause

The figure on this page shows the following table listing the third step in troubleshooting network problems:

Step 3: Test the Theory to Determine Cause
Common steps to determine cause	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 connections. Contact the network administrator. Ping your default gateway. Access a remote web page such as http://www.cisco.com

6.11.1 Applying the Troubleshooting Process to Networks >6.11.1.4 Establish a Plan of Action to Resolve the Problem and Implement the Solution

The figure on this page shows the following table listing the fourth step in troubleshooting network problems:

Step 4: Establish a Plan of Action to Resolve the Problem and Implement the Solution
If no solution is achieved in the previous step, further research is needed to implement the solution	Helpdesk repair logs Other technicians Manufacture FAQ websites Technical websites News Groups Computer Manuals Device Manuals Online forums Internet searches

6.11.1 Applying the Troubleshooting Process to Networks >6.11.1.5 Verify Full System Functionality and Implement Preventative Measures

The figure on this page shows the following table listing the fifth step in troubleshooting network problems:

Step 5: Verify Full System Functionality and Implement Preventative Measures

Verify full functionality

Use ipconfig /all command to display IP address information for all network adapters. Use Ping to check network connectivity. It will send a packet to the specified address and display response information. Use NSLookup to query an internet domain name server. It will return a list of hosts in a domain or the information for one host. Use Tracert to determine the route taken by the packets when they travel across the network. It will show where communications between your computer and another computer are having difficulty. Use net view to display a list of computers in a workgroup. It will show the available shared resources on a network.

6.11.1 Applying the Troubleshooting Process to Networks >6.11.1.6 Document Findings, Actions, and Outcomes

The figure on this page shows the following table listing the sixth step in troubleshooting network problems:

Step 6: Document Findings, Actions, and Outcomes
Document your findings, actions, and outcomes	Discuss the solution implemented with the customer Have the customer verify problems has been solved Provide the customer with all paperwork Document the steps taken to solve the problem in the work order and technician's journal Document any components used in repair, Document the time spent to solve the problem

6.11.2 Common Problems and Solutions for Networks >6.11.2.1 Identify Common Problems and Solutions

The figure on this page shows the following table listing common network problems and solutions:

Identify the Problem	Probable Cause	Possible Solutions
NIC LED lights are not lit.	The network cable is unplugged, bad, or damaged.	Reconnect or replace the network connection to the computer.
User cannot telnet into a remote device.	The remote device is not configured for Telnet access. Telnet is not allowed from the user or a particular network.	Configure the remote device for Telnet access. Allow Telnet access from the user or network.
Older laptop cannot detect the wireless router.	The wireless router/access point is configured with a different 802.11 protocol. The SSID is not being broadcast. The wireless NIC in the laptop is disabled.	Configure the wireless router with a compatible protocol for the laptop. Configure the wireless router to broadcast the SSID. Enable the wireless NIC in the laptop.
Computer has an IP address of 169.254.x.x	The network cable is unplugged. The router is powered off or the connection is bad. The NIC is bad.	Reconnect the network cable. Ensure the router is powered on and is properly connected to the network. Replace the NIC. Release and renew the IP address on the computer.
Remote device does not respond to a ping request.	Windows firewall disables ping by default. The remote device is configured to not respond to ping requests.	Set the firewall to enable the ping protocol. Configure the remote device to respond to the ping request.
One user can log into the local network but cannot access the internet.	The gateway address is incorrect.	Ensure the correct gateway address is assigned to the NIC.
The network is fully functional and the wireless laptop connection is enabled, but the laptop cannot connect to the network.	The laptop wireless capability is turned off. The external wireless antenna is misaligned. The laptop is out of wireless range. Interference from other wireless devices using the same frequency range.	Enable laptop wireless capability using the wireless NIC property or the Fn key along with the multi purpose key. Realign the external wireless antenna to pick up the wireless signal. Move closer to the wireless router/access point. Change wireless router to a different channel.
A windows 7 computer, just connected to a network with only Windows 7 computers, cannot view shared resources.	Incorrect workgroup. Incorrect network location. Has not joined the homegroup. Network discovery and File sharing is turned off.	Change workgroup name. Change network location to Home network. Join the Homegroup. Turn on Network discovery and File sharing.
A user cannot map a drive over the network	Incorrect workgroup. Network Discovery and file sharing is turned off.	Change workgroup name. Turn on Network Discovery and file sharing.

6.12 Networks

6.12.1 Summary >6.12.1.1 Summary

The image on this page shows a data centre with banks of computer servers, routers, and switches on the left and right with a passageway running between them in the centre of the image. There are two people standing behind the nearest banks of servers, one on the left and one on the right. The person on the right is handing the end of an Ethernet cable, across the passageway, to the person on the left.

End of Chapter 6: Networks.

Next - Chapter 7: Laptops.