CCNA2 Module 3 Lab Answers

Activity 3.5.2: Subnetting Scenario 1 (Instructor Version)

Topology Diagram

Addressing Table

Device Interface IP Address Subnet Mask Default Gateway

Fa0/1 192.168.9.193 255.255.255.224 N/A

S0/0/0 192.168.9.129 255.255.255.224 N/AHQ

S0/0/1 192.168.9.161 255.255.255.224 N/A

Fa0/0 192.168.9.65 255.255.255.224 N/A

Fa0/1 192.168.9.97 255.255.255.224 N/ABRANCH1

S0/0/0 192.168.9.158 255.255.255.224 N/A

Fa0/0 192.168.9.33 255.255.255.224 N/A

Fa0/1 192.168.9.1 255.255.255.224 N/ABRANCH2

S0/0/1 192.168.9.190 255.255.255.224 N/A

PC1 NIC 192.168.9.222 255.255.255.224 192.168.9.193

PC2 NIC 192.168.9.126 255.255.255.224 192.168.9.97

PC3 NIC 192.168.9.94 255.255.255.224 192.168.9.65

PC4 NIC 192.168.9.62 255.255.255.224 192.168.9.33

PC5 NIC 192.168.9.30 255.255.255.224 192.168.9.1

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CCNA ExplorationRouting Protocols and Concepts: Introduction to Dynamic Routing Protocols Activity 3.5.2: Subnetting Scenario 1

Learning Objectives Upon completion of this lab, you will be able to:

Determine the number of subnets needed.Determine the number of hosts needed.Design an appropriate addressing scheme.Assign addresses and subnet mask pairs to device interfaces and hosts.Examine the use of the available network address space.Determine how static routing could be applied to the network.

ScenarioIn this lab, you have been given the network address 192.168.9.0/24 to subnet and provide the IP addressing for the network shown in the Topology Diagram. The network has the following addressingrequirements:

The BRANCH1 LAN 1 will require 10 host IP addresses.The BRANCH1 LAN 2 will require 10 host IP addresses.The BRANCH2 LAN 1 will require 10 host IP addresses.The BRANCH2 LAN 2 will require 10 host IP addresses.The HQ LAN will require 20 host IP addresses. The link from HQ to BRANCH1 will require an IP address for each end of the link.The link from HQ to BRANCH2 will require an IP address for each end of the link.

(Note: Remember that the interfaces of network devices are also host IP addresses and are includedin the above addressing requirements.)

Task 1: Examine the Network Requirements.Examine the network requirements and answer the questions below. Keep in mind that IP addresses willbe needed for each of the LAN interfaces.

How many subnets are needed? _____7_____

What is the maximum number of IP addresses that are needed for a single subnet? _____20_____

How many IP addresses are needed for each of the branch LANs? _____10_____

What is the total number of IP addresses that are needed? _____64_____

Task 2: Design an IP Addressing Scheme.

Step 1: Subnet the 192.168.9.0 network into the appropriate number of subnets.What will the subnet mask be for the subnetworks? _____________255.255.255.224 or /27_____________

How many usable host IP addresses are there per subnet? _____30_____



Fill in the following chart with the subnet information.

SubnetNumber Subnet Address First Usable

Host AddressLast Usable

Host AddressBroadcastAddress

0 192.168.9.0 192.168.9.1 192.168.9.30 192.168.9.311 192.168.9.32 192.168.9.33 192.168.9.62 192.168.9.632 192.168.9.64 192.168.9.65 192.168.9.94 192.168.9.953 192.168.9.96 192.168.9.97 192.168.9.126 192.168.9.1274 192.168.9.128 192.168.9.129 192.168.9.158 192.168.9.1595 192.168.9.160 192.168.9.161 192.168.9.190 192.168.9.1916 192.168.9.192 192.168.9.193 192.168.9.222 192.168.9.2237 192.168.9.224 192.168.9.225 192.168.9.254 192.168.9.255

Step 2: Assign the subnets to the network shown in the Topology Diagram.When assigning the subnets, keep in mind that routing will need to occur to allow information to be sentthroughout the network. The subnets will be assigned to the networks to allow for route summarization on each of the routers.

1. Assign first subnet (lowest subnet) to the LAN connected to the Fa0/1 interface of BRANCH2.What is the subnet address? __________192.168.9.0 /27__________

2. Assign second subnet to LAN connected to the Fa0/1 interface of BRANCH2. What is the subnetaddress? __________192.168.9.32 /27__________

3. Assign third subnet to LAN connected to the Fa0/0 interface of BRANCH1. What is the subnetaddress?__________192.168.9.64 /27__________

4. Assign fourth subnet to LAN connected to the Fa0/1 interface of BRANCH1. What is the subnetaddress?__________192.168.9.96 /27__________

5. Assign fifth subnet to the WAN link from HQ to BRANCH1. What is the subnetaddress?__________192.168.9.128 /27__________

6. Assign sixth subnet to the WAN link from HQ to BRANCH2. __________192.168.9.160/27__________

7. Assign seventh subnet to LAN connected to the Fa0/1 interface of HQ. What is the subnetaddress? __________192.168.9.192 /27__________

Note: The highest subnet will not be required in this topology.

Task 3: Assign IP Addresses to the Network DevicesAssign the appropriate addresses to the device interfaces. Document the addresses to be used in the Addressing Table provided under the Topology Diagram.

Step 1: Assign addresses to the HQ router.1. Assign the first valid host address in the HQ LAN subnet to the LAN interface.

2. Assign the first valid host address in link from HQ to BRANCH1 subnet to the S0/0/0 interface.

3. Assign the first valid host address in link from HQ to BRANCH2 subnet to the S0/0/1 interface.

Step 2: Assign addresses to the BRANCH1 router.1. Assign the first valid host address in the BRANCH1 LAN 1 subnet to the Fa0/0 LAN interface.

2. Assign the first valid host address in the BRANCH1 LAN 2 subnet to the Fa0/1 LAN interface.

3. Assign the last valid host address in link from HQ to BRANCH1 subnet to the WAN interface.



Step 3: Assign addresses to the BRANCH2 router.1. Assign the first valid host address in the BRANCH2 LAN 1 subnet to the Fa0/0 LAN interface.

2. Assign the first valid host address in the BRANCH2 LAN 2 subnet to the Fa0/1 LAN interface.

3. Assign the last valid host address in link from HQ to BRANCH2 subnet to the WAN interface.

Step 4: Assign addresses to the host PCs. 1. Assign the last valid host address in the HQ LAN subnet to PC1.

2. Assign the last valid host address in the BRANCH1 LAN 1 subnet to PC2.




Task 4: Test the Network Design. Apply your addressing scheme to the Packet Tracer file that has been supplied with this lab. Check to see that all devices on directly connected networks can ping each other.

Task 5: Reflection How many IP address in the 192.168.9.0 network are unused or unusable in this design?_____192_____

What would the command be to add a default static route on the WAN interface of the BRANCH1 router?

___________________________________________________________________________________ip route 0.0.0.0 0.0.0.0 serial 0/0

Can both of the BRANCH1 LANs be summarized into one route on the HQ router? _____yes_____

What would be the command used to add this summary route to the routing table?

___________________________________________________________________________________ip route 192.168.9.64 255.255.255.192 serial 0/0

Can both of the BRANCH2 LANs be summarized into one route on the HQ router? _____yes_____


___________________________________________________________________________________ip route 192.168.9.0 255.255.255.192 serial 0/1

Can the HQ LAN and both of the BRANCH1 LANs be summarized into one route on the BRANCH2 router? This summarized route should also include the link between the HQ and BRANCH1 routers.

_____yes_____


___________________________________________________________________________________ip route 192.168.9.0 255.255.255.128 serial 0/0



Topology Diagram



Addressing Table


Fa0/0 172.16.16.1 255.255.254.0 N/A

S0/0/0 172.16.14.1 255.255.254.0 N/A

S0/0/1 172.16.18.1 255.255.254.0 N/AHQ

S0/0/2 209.165.200.226 255.255.255.224 N/A

Fa0/0 172.16.12.1 255.255.254.0 N/A

S0/0/0 172.16.15.254 255.255.254.0 N/A

S0/0/1 172.16.8.1 255.255.254.0 N/AWest

S0/0/2 172.16.10.1 255.255.254.0 N/A

Fa0/0 172.16.20.1 255.255.254.0 N/A

S0/0/0 172.16.19.254 255.255.254.0 N/A

S0/0/1 172.16.22.1 255.255.254.0 N/AEast

S0/0/2 172.16.24.1 255.255.254.0 N/A

Fa0/0 172.16.2.1 255.255.254.0 N/A

S0/0/0 172.16.9.254 255.255.254.0 N/ABranch 1

S0/0/1 172.16.6.1 255.255.254.0 N/A

Fa0/0 172.16.4.1 255.255.254.0 N/A

S0/0/0 172.16.11.254 255.255.254.0 N/ABranch 2

S0/0/1 172.16.7.254 255.255.254.0 N/A

Fa0/0 172.16.28.1 255.255.254.0 N/A

S0/0/0 172.16.23.254 255.255.254.0 N/ABranch 3

S0/0/1 172.16.26.1 255.255.254.0 N/A

Fa0/0 172.16.30.1 255.255.254.0 N/A

S0/0/0 172.16.25.254 255.255.254.0 N/ABranch 4

S0/0/1 172.16.27.254 255.255.254.0 N/A

PC1 NIC 172.16.17.254 255.255.254.0 172.16.16.1

PC2 NIC 172.16.13.254 255.255.254.0 172.16.12.1

PC3 NIC 172.16.21.254 255.255.254.0 172.16.20.1

PC4 NIC 172.16.3.254 255.255.254.0 172.16.2.1

PC5 NIC 172.16.5.254 255.255.254.0 172.16.4.1

PC6 NIC 172.16.29.254 255.255.254.0 172.16.28.1

PC7 NIC 172.16.31.254 255.255.254.0 172.16.30.1




Determine the number of subnets needed.Determine the number of hosts needed.Design an appropriate addressing scheme.Assign addresses and subnet mask pairs to device interfaces and hosts.Examine the use of the available network address space.Determine how static routing could be applied to the network.


The Branch 1 LAN will require 100 host IP addresses.The Branch 2 LAN will require 100 host IP addresses.The Branch 3 LAN will require 100 host IP addresses.The Branch 4 LAN will require 100 host IP addresses.The West LAN will require 400 hosts.The East LAN will require 400 hosts.The HQ LAN will require 500 host IP addresses.The links between each of the routers will require an IP address for each end of the link.


The IP addresses for the link from the HQ router to the ISP have already been assigned. The Serial 0/2 address of the HQ router is 209.165.200.226/27. The IP address of the Serial 0/0 of the ISP router is209.165.200.227/27.





How many IP addresses are needed for all of the connections between routers? _____16_____


Task 2: Design an IP Addressing Scheme.

Step 1: Subnet the 172.16.0.0 network into the appropriate number of subnets.What will the subnet mask be for the subnetworks? __________255.255.254.0 or /23_______________

How many usable host IP addresses are there per subnet? _____510_____



Fill in the following chart with the subnet information.

SubnetNumber

Subnet IP First Usable Host IP Last Usable Host IP BroadcastAddress

0 172.16.0.0 172.16.0.1 172.16.1.254 172.16.1.2551 172.16.2.0 172.16.2.1 172.16.3.254 172.16.3.2552 172.16.4.0 172.16.4.1 172.16.5.254 172.16.5.2553 172.16.6.0 172.16.6.1 172.16.7.254 172.16.7.2554 172.16.8.0 172.16.8.1 172.16.9.254 172.16.9.2555 172.16.10.0 172.16.10.1 172.16.11.254 172.16.11.2556 172.16.12.0 172.16.12.1 172.16.13.254 172.16.13.2557 172.16.14.0 172.16.14.1 172.16.15.254 172.16.15.2558 172.16.16.0 172.16.16.1 172.16.17.254 172.16.17.2559 172.16.18.0 172.16.18.1 172.16.19.254 172.16.19.255

10 172.16.20.0 172.16.20.1 172.16.21.254 172.16.21.25511 172.16.22.0 172.16.22.1 172.16.23.254 172.16.23.25512 172.16.24.0 172.16.24.1 172.16.25.254 172.16.25.25513 172.16.26.0 172.16.26.1 172.16.27.254 172.16.27.25514 172.16.28.0 172.16.28.1 172.16.29.254 172.16.29.25515 172.16.30.0 172.16.30.1 172.16.31.254 172.16.31.255

Step 2: Assign the subnets to the network shown in the Topology Diagram.When assigning the subnets, keep in mind that routing will need to occur to allow information to be sentthroughout the network. The subnets will be assigned to the networks to allow for route summarization on each of the routers.

Note: The lowest subnet (subnet 0) will not be assigned in this lab. You should start assigning with the second lowest subnet (subnet 1).

1. Assign subnet 1 to the Branch 1 LAN subnet: __________172.16.2.0 /23__________

2. Assign subnet 2 to the Branch 2 LAN subnet: __________172.16.4.0 /23__________

3. Assign subnet 3 to the link between the Branch 1 and Branch 2 routers: __________172.16.6.0/23__________

4. Assign subnet 4 to the link between the Branch 1 and West routers: __________172.16.8.0/23__________

5. Assign subnet 5 to the link between the Branch 2 and West routers: __________172.16.10.0/23__________

6. Assign subnet 6 to the West LAN subnet: __________172.16.12.0 /23__________

7. Assign subnet 7 to the link between the West and HQ routers: __________172.16.14.0/23__________

8. Assign subnet 8 to the HQ LAN subnet: __________172.16.16.0 /23__________

9. Assign subnet 9 to the link between the HQ and East routers: __________172.16.18.0/23__________

10. Assign subnet 10 to the East LAN subnet: __________172.16.20.0 /23__________

11. Assign subnet 11 to the link between the Branch 3 and East routers: __________172.16.22.0/23__________

12. Assign subnet 12 to the link between the Branch 4 and East routers: __________172.16.24.0/23__________



13. Assign subnet 13 to the link between the Branch 3 and Branch 4 routers:__________172.16.26.0 /23__________

14. Assign subnet 14 to the Branch 3 subnet: __________172.16.28.0 /23__________

15. Assign subnet 15 to the Branch 4 subnet: __________172.16.30.0 /23__________

Task 3: Assign IP Addresses to the Network Devices.Assign the appropriate addresses to the device interfaces. Document the addresses to be used in the Addressing Table provided under the Topology Diagram.

Step 1: Assign addresses to the HQ router.1. Assign the first valid host address in the HQ LAN subnet to the LAN interface.

2. Assign the first valid host address in the link from HQ to West subnet to the S0/0/0 interface.

3. Assign the first valid host address in the link from HQ to East subnet to the S0/0/1 interface.

Step 2: Assign addresses to the West router. 1. Assign the first valid host address in the West LAN subnet to the LAN interface.

2. Assign the last valid host address in the link from HQ to West subnet to the S0/0/0 interface.

3. Assign the first valid host address in the link from West to Branch 1 subnet to the S0/0/1 interface.

4. Assign the first valid host address in the link from West to Branch 2 subnet to the S0/0/2 interface.

Step 3 Assign addresses to the East router.1. Assign the first valid host address in the East LAN subnet to the LAN interface.

2. Assign the last valid host address in the link from HQ to East subnet to the S0/0/0 interface.

3. Assign the first valid host address in the link from East to Branch 3 subnet to the S0/0/1 interface.

4. Assign the first valid host address in the link from East to Branch 4 subnet to the S0/0/2 interface.

Step 4 Assign addresses to the Branch 1 router.1. Assign the first valid host address in the Branch 1 LAN subnet to the LAN interface.

2. Assign the last valid host address in the link from West to Branch 1 subnet to the S0/0/0 interface.

3. Assign the first valid host address in the link from Branch 1 to Branch 2 subnet to the S0/0/1 interface.


2. Assign the last valid host address in the link from West to Branch 2 subnet to the S0/0/0 interface.

3. Assign the last valid host address in the link from Branch 1 to Branch 2 subnet to the S0/0/1 interface.


2. Assign the last valid host address in the link from East to Branch 3 subnet to the S0/0/0 interface.



3. Assign the first valid host address in the link from Branch 3 to Branch 4 subnet to the S0/0/1 interface.


2. Assign the last valid host address in the link from East to Branch 4 subnet to the S0/0/0 interface.

3. Assign the last valid host address in the link from Branch 3 to Branch 4 subnet to the S0/0/1 interface.

Step 8 Assign addresses to the host PCs 1. Assign the last valid host address in the HQ LAN subnet to PC1.

2. Assign the last valid host address in the West LAN subnet to PC2.

3. Assign the last valid host address in the East 1 LAN subnet to PC3.

4. Assign the last valid host address in the Branch 1 LAN subnet to PC4.




Task 4: Test the Network Design. Apply your addressing scheme to the Packet Tracer file that has been supplied with this lab. Check to see that all devices on directly connected networks can ping each other.

Task 5: Reflection How many IP address in the 172.16.0.0 network are wasted in this design? _____63820_____

What would the command be to add a default static route for your entire network design from the HQ router to the ISP router?

___________________________________________________________________________________ip route 0.0.0.0 0.0.0.0 209.165.200.227

Can the West, Branch 1, and Branch 2 networks be summarized into one route on the HQ router? Thissummarized route should also include the serial links that connect the West, Branch 1, and Branch 2 routers. _____yes_____


___________________________________________________________________________________ip route 172.16.0.0 255.255.240.0 serial 0/0

Can the East, Branch 3, and Branch 4 networks be summarized into one route on the HQ router? Thissummarized route should also include the serial links that connect the East, Branch 3, and Branch 4 routers. _____yes_____


___________________________________________________________________________________ip route 172.16.16.0 255.255.240.0 serial 0/1



What would the command be to add a default static route on the West router to send traffic for all unknown destinations to the HQ router?

___________________________________________________________________________________ip route 0.0.0.0 0.0.0.0 serial 0/0

What would the command be to add a default static route on the East router to send traffic for allunknown destinations to the HQ router?

___________________________________________________________________________________ip route 0.0.0.0 0.0.0.0 serial 0/0

Can the Branch 1 and Branch 2 networks be summarized into one route on the West router? Thissummarized route should also include the serial link that connects the Branch 1 and Branch 2 routers._____yes_____

What would be the command used to add this summary route to the routing table? Use the S0/0/1 interface of the West router as the exit interface.

___________________________________________________________________________________ip route 172.16.0.0 255.255.248.0 serial 0/1

Can the Branch 3 and Branch 4 networks be summarized into one route on the East router? Thissummarized route should also include the serial link that connects the Branch 3 and Branch 4 routers._____yes_____

What would be the command used to add this summary route to the routing table? Use the S0/0/1 interface of the East router as the exit interface.

___________________________________________________________________________________ip route 172.16.24.0 255.255.248.0 serial 0/1

The Branch 1 router requires a static route for traffic destined for Branch 2. All other traffic should be sentto the West router using a default static route. What commands would be used to accomplish this?

___________________________________________________________________________________

___________________________________________________________________________________ip route 172.16.4.0 255.255.254.0 serial 0/1

ip route 0.0.0.0 0.0.0.0 serial 0/0

The Branch 2 router requires a static route for traffic destined for Branch 1. All other traffic should be sentto the West router using a default static route. What commands would be used to accomplish this?

___________________________________________________________________________________

___________________________________________________________________________________ip route 172.16.2.0 255.255.254.0 serial 0/1

ip route 0.0.0.0 0.0.0.0 serial 0/0



The Branch 3 router requires a static route for traffic destined for Branch 4. All other traffic should be sentto the East router using a default static route. What commands would be used to accomplish this?

___________________________________________________________________________________

___________________________________________________________________________________ip route 172.16.30.0 255.255.254.0 serial 0/1

ip route 0.0.0.0 0.0.0.0 serial 0/0

The Branch 4 router requires a static route for traffic destined for Branch 3. All other traffic should be sentto the East router using a default static route. What commands would be used to accomplish this?

___________________________________________________________________________________

___________________________________________________________________________________ip route 172.16.28.0 255.255.254.0 serial 0/1

ip route 0.0.0.0 0.0.0.0 serial 0/0



Topology Diagram

Addressing Table


Fa0/0 N/A

S0/0/0 N/AHQ

S0/0/1 N/A

Fa0/0 N/A

Fa0/1 N/A

S0/0/0 N/ABRANCH1

S0/0/1 N/A

Fa0/0 N/A

Fa0/1 N/A

S0/0/0 N/ABRANCH2

S0/0/1 N/A

PC1 NIC

PC2 NIC

PC3 NIC

PC4 NIC

PC5 NIC



Instructor Note: This lab is impossible to complete with fixed-length subnet masking. Use this lab as a scaffolding exercise to link the student to the concept of VLSM, which is discussed in Chapter 6. Avoid offering the student any help in solving the problem of not having enough address space.


Determine the number of subnets needed.Determine the number of hosts needed.Design an appropriate addressing scheme.Conduct research to find a possible solution.


The BRANCH1 LAN 1 will require 15 host IP addresses.The BRANCH1 LAN 2 will require 15 host IP addresses.The BRANCH2 LAN 1 will require 15 host IP addresses.The BRANCH2 LAN 2 will require 15 host IP addresses.The HQ LAN will require 30 host IP addresses. The link from HQ to BRANCH1 will require an IP address for each end of the link.The link from HQ to BRANCH2 will require an IP address for each end of the link.The link from HQ to Branch 3 will require an IP address for each end of the link.







Task 2: Design an IP Addressing Scheme Subnet the 192.168.1.0/24 network into the appropriate number of subnets.

Can the 192.168.1.0/24 network be subnetted to fit the network requirements? _____no_____

If the “number of subnets” requirement is met, what is the maximum number of hosts per subnet?_____30_____

If the “maximum number of hosts” requirement is met, what is the number of subnets that will be available to use? _____4_____



Task 3: Reflection You do not have enough address space to implement an addressing scheme. Research this problem andpropose a possible solution. Increasing the size of your original address space is not an acceptablesolution. (Hint: We will discuss solutions to this problem in Chapter 6.)

____________________________________________________________________________

____________________________________________________________________________

____________________________________________________________________________

Attempt to implement your solution using Packet Tracer. Successful implementation of a solution requiresthat:

Only the 192.168.1.0/24 address space is used. PCs and routers can ping all IP addresses.


Documents

CCNA2 Module 3 Lab Answers