# 8.1.4.7 Packet Tracer – Subnetting Scenario 1 - Answers

### Topology

R1 G0/0 192.168.100.1 255.255.255.224 N/A
G0/1 192.168.100.33 255.255.255.224 N/A
S0/0/0 192.168.100.129 255.255.255.224 N/A
R2 G0/0 192.168.100.65 255.255.255.224 N/A
G0/1 192.168.100.97 255.255.255.224 N/A
S0/0/0 192.168.100.158 255.255.255.224 N/A
S1 VLAN 1 192.168.100.2 255.255.255.224 192.168.100.1
S2 VLAN 1 192.168.100.34 255.255.255.224 192.168.100.33
S3 VLAN 1 192.168.100.66 255.255.255.224 192.168.100.65
S4 VLAN 1 192.168.100.98 255.255.255.224 192.168.100.97
PC1 NIC 192.168.100.30 255.255.255.224 192.168.100.1
PC2 NIC 192.168.100.62 255.255.255.224 192.168.100.33
PC3 NIC 192.168.100.94 255.255.255.224 192.168.100.65
PC4 NIC 192.168.100.126 255.255.255.224 192.168.100.97

### Objectives

• Part 1: Design an IP Addressing Scheme
• Part 2: Assign IP Addresses to Network Devices and Verify Connectivity

### Scenario

In this activity, you are given the network address of 192.168.100.0/24 to subnet and provide the IP addressing for the network shown in the topology. Each LAN in the network requires enough space for, at least, 25 addresses for end devices, the switch and the router. The connection between R1 to R2 will require an IP address for each end of the link.

#### Part 1: Design an IP Addressing Scheme

##### Step 1: Subnet the 192.168.100.0/24 network into the appropriate number of subnets.

a. Based on the topology, how many subnets are needed?
5

b. How many bits must be borrowed to support the number of subnets in the topology table?
3 bits

c. How many subnets does this create?
2^3 = 8 subnets (support subnet zero)

d. How many usable hosts does this create per subnet?
2^5 – 2 = 30 hosts

Note: If your answer is less than the 25 hosts required, then you borrowed too many bits.

e. Calculate the binary value for the first five subnets. The first subnet is already shown.

```Net 0: 192 . 168 . 100 .  0   0   0   0   0   0   0   0

Net 1: 192 . 168 . 100 . ___ ___ ___ ___ ___ ___ ___ ___
Net 1: 192 . 168 . 100 .  0   0   1   0   0   0   0   0

Net 2: 192 . 168 . 100 . ___ ___ ___ ___ ___ ___ ___ ___
Net 2: 192 . 168 . 100 .  0   1   0   0   0   0   0   0

Net 3: 192 . 168 . 100 . ___ ___ ___ ___ ___ ___ ___ ___
Net 3: 192 . 168 . 100 .  0   1   1   0   0   0   0   0

Net 4: 192 . 168 . 100 . ___ ___ ___ ___ ___ ___ ___ ___
Net 4: 192 . 168 . 100 .  1   0   0   0   0   0   0   0```

f. Calculate the binary and decimal value of the new subnet mask.

```11111111.11111111.11111111. ___ ___ ___ ___ ___ ___ ___ ___
11111111.11111111.111111111. 1   1   1   0   0   0   0   0
255  .   255  .   255  . ______
255  .   255  .   255  .  224```

g. Fill in the Subnet Table, listing the decimal value of all available subnets, the first and last usable host address, and the broadcast address. Repeat until all addresses are listed.

Note: You may not need to use all rows.

#### Subnet Table

0 192.168.100.0 192.168.100.1 192.168.100.30 192.168.100.31
1 192.168.100.32 192.168.100.33 192.168.100.62 192.168.100.63
2 192.168.100.64 192.168.100.65 192.168.100.94 192.168.100.95
3 192.168.100.96 192.168.100.97 192.168.100.126 192.168.100.127
4 192.168.100.128 192.168.100.129 192.168.100.158 192.168.100.159
5 192.168.100.160 192.168.100.161 192.168.100.190 192.168.100.191
6 192.168.100.192 192.168.100.193 192.168.100.222 192.168.100.223
7 192.168.100.224 192.168.100.225 192.168.100.254 192.168.100.255
8
9
10
##### Step 2: Assign the subnets to the network shown in the topology.

a. Assign Subnet 0 to the LAN connected to the GigabitEthernet 0/0 interface of R1: –
192.168.100.0 /27

b. Assign Subnet 1 to the LAN connected to the GigabitEthernet 0/1 interface of R1: –
192.168.100.32 /27

c. Assign Subnet 2 to the LAN connected to the GigabitEthernet 0/0 interface of R2: –
192.168.100.64 /27

d. Assign Subnet 3 to the LAN connected to the GigabitEthernet 0/1 interface of R2: –
192.168.100.96 /27

e. Assign Subnet 4 to the WAN link between R1 to R2: –
192.168.100.128 /27

##### Step 3: Document the addressing scheme.

Fill in the Addressing Table using the following guidelines:

a. Assign the first usable IP addresses to R1 for the two LAN links and the WAN link.

b. Assign the first usable IP addresses to R2 for the LANs  links. Assign the last usable IP address for the WAN link.

c. Assign the second usable IP addresses to the switches.

d. Assign the last usable IP addresses to the hosts.

#### Part 2: Assign IP Addresses to Network Devices and Verify Connectivity

Most of the IP addressing is already configured on this network. Implement the following steps to complete the addressing configuration.

##### Instructions
```R1(config)#interface gigabitEthernet 0/0
R1(config-if)#no shutdown
R1(config-if)#exit

R1(config)#interface gigabitEthernet 0/1
R1(config-if)#no shutdown```
```S3>enable
S3#configure terminal
S3(config)#interface vlan 1