MODULE 3 – PHYSICAL COMPONENTS OF A NETWORK
MODULE OVERVIEW
Single Diagram
Diagram 1. Tabular
Physical Components of a Network
After completing this chapter, students will be able to perform tasks relating to:
- Configuring a Network Interface Card (NIC)
- Topologies
- Media Types
- Devices
MODULE 3.1– CONFIGURING A NETWORK INTERFACE CARD
SECTION 3.1.1: WHAT IS A NIC?
Three Diagrams
Diagram 1, Pictorial
Network Interface Card
Displays top view of a Typical NIC (With PCI connectors)
Diagram 2, Pictorial
Network Interface Card
Displays top view of a Typical NIC (With PCI connectors)
Diagram 3, Pictorial
Network Interface Card
Displays end (Connector) view of a Typical NIC (With RJ-45 and Serial ports visable)
SECTION 3.1.2: SETTING THE IP ADDRESS
Single Diagram
Diagram 1, Screenshot
Specifying the IP Address in Windows 2000
The Internet Protocol (TCP/IP) Properties dialog box
Displays a single open window, 'Internet Protocol (TCP/IP) Properties'
This window shows the IP address, Subnet mask and Default gateway specifications.
(The option to obtain an IP address automatically is also available, along with DNS server
addresses)
SECTION 3.1.3: DHCP SERVERS
Two Diagrams
Diagram 1, Screenshot
Configuring DHCP Service in Windows 2000
Displays a single open window - 'DHCP'
Showing DHCP tree and Configuration information
Diagram 2, Screenshot
Using DHCP in Windows 2000
Displays a single open window - 'Internet Protocol (TCP/IP) Properties'
Options to automatically obtain IP and DNS server addresses are selected.
SECTION 3.1.4: DOMAIN NAME SYSTEM
Three Diagrams
Diagram 1, Relational/Descriptive
Domain Name Server Functions
A DNS Server resolves the Post Office name of an e-mail address.
A star network with a central switch is displayed. Two clients, a DNS server and a router are
connected. Client A wants to send an e-mail to JJones@cisco.com , the DNS server resolves
the cisco.com to the required IP address, and returns the address to the client.
Diagram 2, Screenshot
Configuring the DNS server in Windows 2000
Displays a single open window - 'DHCP'
Shows the DNS tree and Server configuration information
Diagram 3, Screenshot
Specifying DNS in Windows 2000
Displays a single open window - 'Internet Protocol (TCP/IP) Properties'
The manual DNS server entry is selected, allowing the administrator to specify a preferred and
a alternative DNS server.
SECTION 3.1.5: DEFAULT GATEWAY
Single Diagram
Diagram 1, Relational
Setting up a Default Gateway - Windows 2000
Displays four workstations and two servers connected via a central bus to a router. The
address of this near-end router is the Default Gateway. (Buses will be examined Further on)
MODULE 3.2 – TOPOLOGIES
SECTION 3.2.1: THE NETWORK TOPOLOGY
Single Diagram
Diagram 1, Relational
A Network Topology Diagram
This Diagram displays several different types of network topologies, including the star, bus,
and ring. Complex Diagram
SECTION 3.2.2: PHYSICAL VERSUS LOGICAL TOPOGOGY
Two Diagrams
Diagram 1, Office Floor Plan
Physical Topology Diagram
The floor-plan is divided into the various business departments and offices, the connecting
configurations for the Water supply, Lighting, Power, and air conditioning are shown. Each of
these are connected using the various physical topologies.
Diagram 2, Relational
Logical Topology Diagram
Workstations and Servers are connected in a star formation through a central hub. Regardless
of how the stations are physically located this is how the logical network operates.
Animation - Data is transferred from a workstation to the server and back, in both instances
traversing the hub.
SECTION 3.2.3: IDENTIFYING NETWORK TOPOLOGIES
Nine Diagrams
Diagram 1, Relational
Bus Topology
In bus topology, electrical signals that reach the end of the wire are absorbed by the
terminator.
A bus or cable runs from one terminator to another, the workstations and servers connect
directly to the bus.
Diagram 2, Tabular
Features of Bus Topology
Advantages of Bus Topology
- The thinnet cabling the bus topology uses is quite inexpensive
- The bus topology uses less cable compared to other physical topologies like star or
extended star.
- The bus topology works well for small networks, those with fewer than 10 computers or
Devices
- The bus topology does not need a central device, such as a hub, switch, or router
Disadvantages of Bus Topology
- Terminators must be used or the electrical signals will be corrupted
- Any break or damage on the bus will collapse the whole network
- Only a single file /command/or instruction can be sent at any particular time to avoid data
collisions from multiple transmission sites.
Diagram 3, Relational
Star Topology
A star topology is typically used in Ethernet (10BASE-T, 100BASE-TX, fibre 100BASE-FX etc)
and Token Ring networks, where the centre of the network is a hub, repeater, concentrator, or
switch.
Displays a star configuration network, a central hub surrounded by workstations and servers.
Diagram 4, Relational
Extended Star Topology
Example of an extended star topology when additional hubs are attached to a star
Displays an extended star network, This consists of multiple start networks each connected to
a central star network. (interconnections are via the central hubs)
Diagram 5, Tabular
Advantages and disadvantages of Star topology
Advantages of Star Topology
- The star topology is upgradeable. Adding a new computer is as easy as plugging the cable
that is connected to the new workstation into the hub.
- The star topology is flexible. The layout is easy to modify and new hosts or devices can be
added quickly.
- The Star topology is reliable, if one line of the networking media is broken or shorted, only
the device attached at that point is out of commission and the rest of the LAN remains
functional
- This topology is easy to design and install. The networking media runs out from a central
device like a hub to each workstation or device.
- This topology makes diagnosing problems relatively easy since the problem is localised to
one computer or device.
- This topology allows for more throughput than any other topology.
Disadvantages of Star Topology
- The star topology requires a lot of cable to connect computers since a cable is required
between each device and the central location.
- The star topology is more expensive to build because of the additional cost of cables and
devices like hubs and switches that are needed to run between the central device and each
computer.
Diagram 6, Relational
Single Ring Topology
In single ring topology data moves in one direction
Displays multiple computers in a circle or ring, each computer has two connections, one to the
computer clockwise of its position and a second to the computer anti-clockwise of its position.
Data flows in one direction only (clockwise or anti-clockwise).
Diagram 7, Relational
Dual Ring Topology
In Dual ring topology, data moves in opposite directions in two rings.
Displays multiple computers in a circle or ring, each computer now has four connections. Two
connections to each of the computers clockwise and anti-clockwise from its position. These
multiple connections form two rings which can be used to send data in either direction. It is
important to note that each of the two rings may only transmit in a single direction.
Diagram 8, Relational
Mesh Topology
With Mesh topology, each node is connected to all other nodes on the network for redundancy.
Displays multiple workstations and servers, each device has a direct connection to every other
device.
Diagram 9, Relational
Hybrid Topology
A Star-Bus is one form of hybrid topology.
A hybrid topology is where the previously mentioned topologies are interconnected in some
way.
Displays two separate star networks, interconnected by the central hubs via a bus.
MODULE 3.3 – MEDIA TYPES
SECTION 3.3.1: NETWORKING MEDIA
Single Diagram
Diagram 1, Activity
Types of networking Media
Need to match-up the following media and materials
Media
Copper, Glass, Waves
Materials
Twisted pair (STP, UTP), Coaxial, Fibre-Optic, Wireless
SECTION 3.3.2: TWISTED PAIR CABLE
Six Diagrams
Diagram 3, Pictorial
Twisted Pair Cable
Displays a cut cable, showing the four internal twisted pairs.
Each pair of twisted cables are colour coded, blue/blue-white, brown/brown-white,
green/green-white, and orange/orange-white.
Diagram 2, Pictorial
Twisted Pair Cable with a RJ-45 Connector
Displays the previously mentioned cable with a RJ-45 connector. The individual wires are
inserted and the connector crimped to secure the connector. There are configurations of the
individual wires which determine the type of cable - rollover, crossover or straight through.
Diagram 3, Cable Construction
Shielded Twisted Pair
A shielded twisted pair or STP varies from the Unshielded Twisted Pair UTP in that it has two
layers of electromagnetic shielding. Each pair of wires have a shielding sheath, these four
shielded pairs are further insulated with and overall shielding layer. This overall shield lies
immediately underneath the cable outer jacket.
Diagram 4, Cable Construction
Unshielded Twisted Pair
The UTP (UnshieldedTwisted Pair) consists of an Outer Jacket, surrounding the four colour
codes twisted pairs (eight lines total). The RJ-45 is the common Jack for this type of cable.
Characteristics of UTP (Varies with category, i.e. cat 5, cat 5e, cat 6 etc)
- Speed and throughput: 10-100 Mbps
- Cost Per Node: Least Expensive
- Media and connector size: small
- Maximum cable length 100m (short)
Diagram 5, Pictorial
Crimping Tool
Displays a picture of a common crimping tool used to secure twisted pair cabling to a RJ-45
connector.
Diagram 6, Tabular
Available Categories of UTP Cable
Category 1 Characteristics
- Voice Only, Used in old telephone installations
Category 2 Characteristics
- 4 Mbps, Not recommended for data transmission
Category 3 Characteristics
- 16 Mbps, Lowest recognised data grade; used for most telephone wiring
Category 4 Characteristics
- 20 Mbps, suitable for networking 10Mbps Ethernet networks
Category 5 Characteristics
- 100 Mbps - 1 Gbps, Most popular grade for LAN networking; used for Fast Ethernet (100
Mbps)
Category 5e Characteristics (Note: 'e' stands for 'Enhanced')
- 155 Mbps, Used for Fast Ethernet and 155 Mbps Asynchronous Transfer Mode (ATM)
Category 6 and 7 Characteristics
- 1 Gbps and up, Used for new Gigabit Ethernet Technologies
Text : You do not often see Cat 6, Cat 7, and enhanced Cat 5 mentioned in networking texts
because these new cable types have specifications that have only been recently established.
SECTION 3.3.3: FIBRE OPTIC CABLE
Three Diagrams.
Diagram 1, Descriptive
Fibre-Optic Cable
Displays components of fibre-optic cable construction.
An 'Outer Jacket' surrounds 'Kevlar Reinforcing Material', These intern surround 'Plastic
Shields' which house the actual 'Glass Fibre and Cladding'.
The common connecter type used with optic fibre is termed a 'Multimode Connector'.
Diagram 2, Pictorial
Fibre-Optic Cable
Displays the terminals of fibre-optic cable, similar to a coax connector with the twist on/off
connection however there is an fibre-optic extrusion through the centre of each.
Diagram 3, Tabular
Features of Fibre Optic
Advantages of Fibre Optic
- Not susceptible to electromagnetic or radio frequency interference.
- Longer Distances can be spanned. No need to ground cable when used between buildings.
- Capable of higher data rates than copper media.
Disadvantages
- Expensive labour and material costs
SECTION 3.3.4: WIRELESS
Single Diagram
Diagram 1, Relational
Wireless Media
Wireless media uses transceivers (Concatenation of Transmitter and Receiver), to transmit
and receive data without cables.
Displays four devices, a Workstation, Server, Labtop, and Radio Tower.
Transceivers (Access Points) are found in the workstation, labtop, and server, they
communicate via the radio tower.
MODULE 3.4 – DEVICES
SECTION 3.4.1: HUBS AND REPEATERS
Four Diagrams.
Diagram 1, Device Icons
Hubs and Repeaters
This course uses the following icons to represent hubs and repeaters in network topology
diagrams.
Displays a Hub - a Cube with a single bidirectional arrow (Left/Right) on the upper face, and
multiple small squares in a single line on the front face to represent jack ports.
Displays a Repeater - a Cube which only image is on the front face. This image looks similar to
an air vent grill or a three tiered letterbox.
Diagram 2, Hubs
Four nodes with file sharing capability are represented in a network topology diagram. Four
workstations are connected to a central hub.
Diagram 3, Pictorial
Cisco Hubs
Displays the Port face view of two Cisco Hubs (one 12 port, and one 24 port)
Diagram 4, Relational
Repeaters
Displays two bus networks connected via a repeater (required for long distance signal integrity)
Animation - Displays data being transmitted between workstations on either side of the
repeater.
SECTION 3.4.2: BRIDGES AND SWITCHES
Five Diagrams
Diagram 1, Device Icons
Bridges and Switches
This course uses the following icons to represent Bridges and Switches in network topology
diagrams.
Displays a Bridge - a Cube with a semi circle or bite taken from the top or upper face - Looks
similar to 'Half Pipe' in skateboard or BMX terminology.
Displays a Switch - a Cube which only has an image is on the upper face. This image consists
of four arrows, two pointing left and two right, all arrows point outward (Left and Right).
Diagram 2, Relational
Bridges
Displays two bridged networks connected via a bridge. A bridge divides a network into
'Segments'.
Diagram 3, Pictorial
Cisco Wireless Bridge
Displays a Cisco wireless Bridge with a distinctive antenna at the rear indicating a wireless
device.
Diagram 4, Relational
Switches
Displays four Workstations and a Server connected in star formation using a central Switch
Diagram 5, Pictorial
Cisco Switch
Displays the port side view of a Cisco Switch, Multiple ports can be seen in a line along the
face.
SECTION 3.4.3: ROUTERS
Three Diagrams
Diagram 1, Device Icon
Router
Displays the router icon, This course uses the following icon to represent routers in network
topology diagrams.
Displays a short vertical cylinder, the upper circular face contains four arrows. These arrows
are drawn on the 45 degree lines, the northwest and southeast arrows point to the centre of
the circular face, the northeast and southwest arrows point outward from the centre of the
circular face.
Diagram 2, Network Topology
Segmentation with routers
Routers also divide the network into segments
Displays a central router connected to two servers and four hubs, each hub is connected to
three workstations. Each Hub and Workstation set are separate Segments.
Benefits of using routers for segmentation
- More manageable, greater functionality, Multiple active paths
- Smaller Broadcast domain (Routers also divide Broadcast domains, unlike switches)
- Operates at layers 3 and 4 (of the OSI model)
Diagram 3, Pictorial
Cisco Routers
Displays the front view of three different Cisco routers
SECTION : SUMMARY
Single Diagram
No Relevant Information