IFN507 Network Systems P4: Subnetting and Supernetting
Practical 4
Subnetting and Supernetting
Learning Objectives
Upon completion of this practical, you will be able to:
· Implement a subnetting scheme with Packet Tracer
Scenario
· Lab Activity 1: Implement a network scenario with 4 subnets
· Lab Activity 2: Implement a network scenario with 8 subnets
· More exercises on subnetting and supernetting
Lab Activity 1
In this activity, you will design an IP addressing scheme for the topology shown in Figure 1, and then implement the IP addressing scheme with Packet Tracer.
Activity Objectives:
· Subnet the address space
· Configure IP addresses with Packet Tracer
· Summarise routes through configuring aggregate routes
Topology Diagram
Figure 1 Network Topology
Addressing Table 1
Device
Interface
IP Address
Subnet Mask
Default Gateway
ISP
Se2/0
200.0.0.2
255.255.255.0
N/A
BR
Se2/0
200.0.0.1
255.255.255.0
N/A
Se3/0
N/A
Fa0/0
N/A
HQ
Se2/0
N/A
Fa0/0
N/A
Fa1/0
N/A
DNS
NIC
HTTP
NIC
PC1
NIC
PC2
NIC
PC3
NIC
PC4
NIC
Note: Fill the missing contents in the diagram and in the above Addressing Table 1
Task 1: Subnet the Address Space
Step 1: Examine the network requirements
ABC company has been given the 193.64.33.0/24 address space. You are employed to restructure ABC’s network. You need to set up an addressing scheme that can accommodate for the Internet access and data sharing between the four LANs. Each LAN needs to be on a separate network (subnet).
· The link between routers BR (border) and HQ (headquarters) would need enough IP addresses to support 32 hosts.
· The SE (servers) LAN would need enough IP addresses to support 40 hosts.
· The SA (sales) LAN would need enough IP addresses to support 50 hosts.
· The HR (human resource) LAN would need enough IP addresses to support 60 hosts.
Note: The plan should have equal size subnets and use the smallest subnet sizes that will accommodate the appropriate number of hosts.
Step 2: Consider the following questions when creating your network design
Q1: How many subnets are needed? ___
Q2: How many bits you need to borrow from the host portion for subnetting? ___
Q3: What is the subnet mask used for this subnetting scheme in dotted-decimal notation? ________________ and in slash notation /____
Q4: What is the maximum number of usable IP addresses per subnet? ______
Step 3: Use the following table to list out the subnet information in decimal notation
Subnet
Network
Address
Slash Notation
First Usable
IP Address
Last Usable
IP Address
Broadcast Address
1
2
3
4
Task 2: Assign IP Addresses
1. Fill in Addressing Table 1 with IP addressing information based on the IP address requirements mentioned below:
Subnet 1 is used for the link between routers BR and HQ:
· Assign the first usable IP address of Subnet 1 to the Se3/0 interface of BR.
· Assign the second usable IP address of Subnet 1 to the Se2/0 interface of HQ.
Subnet 2 for the SE LAN:
· Assign the first usable IP address of Subnet 2 to the Fa0/0 interface of BR
· Assign the second usable IP address of Subnet 2 to the DNS server
· Assign the third usable IP address of Subnet 2 to the HTTP server
Subnet 3 for the SA LAN:
· Assign the first usable IP address of Subnet 3 to the Fa0/0 interface of HQ.
· Assign the second usable IP address of Subnet 3 to PC1
· Assign the last usable IP address of Subnet 3 to PC2
Subnet 4 for the HR LAN:
· Assign the first usable IP address of Subnet 4 to the Fa1/0 interface of HQ.
· Assign the second usable IP address of Subnet 4 to PC3
· Assign the last usable IP address of Subnet 4 to PC4
2. Record the dedicated IP addresses in Addressing Table 1.
Task 3: Build the Network Topology
Use Packet Tracer to build the network topology as shown in Figure 1.
Task 4: Configure IP Addressing
Use Addressing Table 1 to configure dedicated IP addresses to the routers and PCs.
Configuring the IP addresses for Router ISP
Router>enable
Router# configure terminal
Router(config)#hostname ISP
ISP(config)# interface Se2/0
ISP(config-if)# ip address 200.0.0.2 255.255.255.0
ISP(config-if)# exit
ISP(config)#
Configuring the IP addresses for Router BR
Configuring the IP addresses for Router HQ
Task 5: Verify Connectivity
Step 1: Test connectivity between directly connected devices
· From router ISP, can you ping the interface Se2/0 of BR successfully? Yes / No
· From router BR, can you ping the interface Se2/0 of HQ successfully? Yes / No
· From each server, can you ping its default gateway successfully? Yes / No
· From each PC, can you ping its default gateway successfully? Yes / No
If you cannot ping successfully at any points, verify the following:
1. Check the cable connection. Have you used the correct Ethernet cables for network connections?
2. Check the router interfaces. Have you activated routers interfaces?
3. Check your IP address configuration. Is your IP address configuration consistent with the Topology Diagram and Addressing Table? Have you configured a default gateway for each PC?
4. Check the subnet information. Is your subnetting scheme calculated correctly?
Step 2: Test connectivity between devices that are NOT on the same network
· From PC4, can you ping PC1 successfully? Yes / No
· From PC4, you are unable to ping the HTTP server successfully. Why?
· From PC4, you are unable to ping the interface Se2/0 of ISP router. Why?
Task 7: Save your work
Click the File menu and then Save your network topology with a file name: Lab4.1.
NOTE: You will need to work with this network topology configuration in the next practical session to resolve the connectivity issue between devices that are NOT on the same network.
Lab Activity 2
In this activity, you will design an IP addressing scheme for the topology shown in Figure 2, and then implement the IP addressing scheme with Packet Tracer.
Activity Objectives:
· Subnet the address space
· Configure IP addresses with Packet Tracer
· Summarise routes through configuring aggregate routes
Topology Diagram
Figure 2 Network Topology
Addressing Table 2
Device
Interface
IP Address
Subnet Mask
Default Gateway
ISP
Se2/0
200.0.0.2
255.255.255.0
N/A
BR
Se2/0
200.0.0.1
255.255.255.0
N/A
Se3/0
N/A
Fa0/0
N/A
Fa1/0
N/A
HQ
Se2/0
N/A
Fa0/0
N/A
Fa1/0
N/A
Fa4/0
N/A
DNS
NIC
HTTP
NIC
SA-PC1
NIC
FS-PC1
NIC
HR-PC1
NIC
Note: Fill the missing contents in the diagram and in the above addressing table 2
Task 1: Subnet the Address Space
Step 1: Examine the network requirements
XYZ company has been given the 193.64.33.0/24 address space. You are employed to restructure XYZ’s network. You need to set up an addressing scheme that can accommodate for the Internet access and data sharing between the LANs. Each LAN needs to be on a separate network (subnet).
· The link between routers BR (border) and HQ (headquarters) would need enough IP addresses to support 16 hosts.
· The SE1 (servers 1) LAN would need enough IP addresses to support 20 hosts.
· The SE2 (servers 2) LAN would need enough IP addresses to support 22 hosts.
· The SA (sales) LAN would need enough IP addresses to support 30 hosts.
· The FS (field service) LAN would need enough IP addresses to support 28 hosts.
· The HR (human resource) LAN would need enough IP addresses to support 18 hosts.
Note: The plan should have equal size subnets and use the smallest subnet sizes that will accommodate the appropriate number of hosts.
Step 2: Consider the following questions when creating your network design
Q1: How many subnets are needed? ______
Q2: How many bits you need to borrow from the host portion for subnetting? ____
Q3: How many subnets will be created when you borrowed the Host-ID bits? _____
Q4: What is the subnet mask used for this addressing scheme in dotted-decimal notation? __________________
Q5: What is the subnet mask used for this addressing scheme in slash notation? /____
Q6: What is the maximum number of usable IP addresses per subnet? ___________
Step 3: Use the following table to list out the subnet information in decimal notation.
Subnet
Network
Address
Slash Notation
First Usable
IP Address
Last Usable
IP Address
Broadcast Address
1
2
3
4
5
6
7
8
Task 2: Assign IP Addresses
1. Fill in Addressing Table 2 with IP addressing information based on the IP address requirements mentioned below:
Subnet 1 for the link between routers BR and HQ:
· Assign the first usable IP address of Subnet 1 to the interface Se3/0 of BR.
· Assign the second usable IP address of Subnet 1 to the interface Se2/0 of HQ.
Subnet 2 for the SE1 LAN:
· Assign the first usable IP address of Subnet 2 to the interface Fa0/0 of BR.
· Assign the second usable IP address of Subnet 2 to the DNS server
Subnet 3 for the SE2 LAN:
· Assign the first usable IP address of Subnet 3 to the interface Fa1/0 of BR.
· Assign the second usable IP address of Subnet 3 to the HTTP server.
Subnet 4 is reserved for future use.
Subnet 5 for the SA LAN:
· Assign the first usable IP address of Subnet 5 to the interface Fa0/0 of HQ.
· Assign the last usable IP address of Subnet 5 to SA-PC1
Subnet 6 for the FS LAN:
· Assign the first usable IP address of Subnet 6 to the interface Fa1/0 of HQ.
· Assign the last usable IP address of Subnet 6 to FS-PC1
Subnet 7 for the HR LAN:
· Assign the first usable IP address of Subnet 7 to the interface Fa4/0 of HQ.
· Assign the last usable IP address of Subnet 7 to HR-PC1
Subnet 8 is reserved for future use.
2. Record the dedicated IP addresses in Addressing Table 2.
Q7: Which two subnets are not used based on this IP addressing assignment? ______________
Task 3: Build the Network Topology
Use Packet Tracer to build the network topology as shown in Figure 2.
Task 4: Configure IP Addressing
Use the Addressing Table 2 to configure dedicated IP addresses to the routers and PCs.
Configuring the IP addresses for Router ISP
Configuring the IP addresses for Router BR
Configuring the IP addresses for Router HQ
Task 5: Verify Connectivity
Step 1: Test connectivity between directly connected devices
· From router ISP, can you ping the interface Se2/0 of BR successfully? Yes / No
· From router BR, can you ping the interface Se2/0 of HQ successfully? Yes / No
· From each server, can you ping its default gateway successfully? Yes / No
· From each PC, can you ping its default gateway successfully? Yes / No
If you cannot ping successfully at any points, verify the following:
1. Check the cable connection. Have you used the correct Ethernet cables for network connections?
2. Check the router interfaces. Have you activated routers interfaces?
3. Check your IP address configuration. Is your IP address configuration consistent with the Topology Diagram and Addressing Table? Have you configured a default gateway for each PC?
4. Check the subnet information. Is your subnetting scheme calculated correctly?
Step 2: Test connectivity between devices that are NOT on the same network
· From HR-PC1, can you ping FS-PC1 successfully? Yes / No
· From HR-PC1, can you ping SA-PC1 successfully? Yes / No
· From HR-PC1, you are unable to ping the HTTP server and the DNS server. Why?
· From HR-PC1, you are unable to ping the interface Se2/0 of ISP successfully? Why?
Task 7: Save your work
Click the File menu and then Save your network topology with a file name: Lab4.2.
NOTE: You will need to work with this network topology configuration in the next practical session to resolve the connectivity issue between devices that are NOT on the same network, so make sure you save this file!!!
More exercises on Subnetting and Supernetting
1. A block of address 194.32.8.0/24 has been given, you need to organise 16 subnets. You need to work out:
· The subnet mask
· The 16 subnets
· The valid host range and broadcast address for each subnet
Subnet mask
Subnet
Network address
Valid host range
Broadcast address
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
2. How to aggregate the following network addresses into one single network address notation?
Network addresses
Aggregated Address
200.100.0.0/24
200.100.1.0/24
200.100.2.0/24
200.100.3.0/24
200.100.4.0/24
200.100.5.0/24
200.100.6.0/24
200.100.7.0/24
200.100.0.0/24
200.100.1.0/24
200.100.2.0/24
200.100.3.0/24
200.100.4.0/24
200.100.5.0/24
200.100.6.0/24
200.100.7.0/24
End of Practical 4
Page 15 of 15
PC1
ISP
Fa1/0
BR
Se2/0 Se2/0
DCE
200.0.0.0/24.2 .1
Fa0/0
ABC Company
ISP
SE SA
HTTP
HQ
Fa0/0
HR
PC2
DNS
PC3 PC4
Se3/0
DCE
Se2/0
ISP
Fa1/0
Se2/0
Se2/0
DCE
200.0.0.0/24
.2
.1
XYZ Company
ISP
SA
HTTP
HQ
Fa0/0
FS
DNS
Se3/0
DCE
Se2/0
.190
SE1
BR
Fa1/0
HR
SA-PC1
FS-PC1
HR-PC1Fa0/0
Fa4/0
SE2