Subnetting Practice # 1

Host IP Address: 195.70.16.93 Six bits have been borrowed to create the required subnets.

What class is this address? Class C

What is the default subnet mask? 255.255.255.0

What is the subnet mask for this host in dotted decimal format? 255.255.255.252

What is the subnet mask for this host in IP Prefix format? /30

How many subnets were created? 64

How many hosts per subnet? 4

How many usable hosts per subnet? 2

Perform the ANDing process on the supplied

host address

Address 11000011.01000110.00010000.01011101

Subnet Mask 11111111.11111111.11111111.11111100

Result 11000011.01000110.00010000.01011100

What is the network address for the supplied host address? 195.70.16.92

What is the broadcast address for the supplied host address? 195.70.16.95

Is the address 195.70.16.159a Network, Host or Broadcast address? Broadcast address

Is the address 195.70.16.28a Network, Host or Broadcast address? Network address

Is the address 195.70.16.58a Network, Host or Broadcast address? Host address

Is the address 195.70.16.164a Network, Host or Broadcast address? Network address

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Subnetting Practice # 2

Host IP Address: 172.16.126.120 Eight bits have been borrowed to create the required subnets.

What class is this address? Class B

What is the default subnet mask? 255.255.0.0

What is the subnet mask for this host in dotted decimal format? 255.255.255.0

What is the subnet mask for this host in IP Prefix format? /24

How many subnets were created? 256

How many hosts per subnet? 256

How many usable hosts per subnet? 254

Perform the ANDing process on the supplied

host address

Address 10101100.00010000.01111110.01111000

Subnet Mask 11111111.11111111.11111111.00000000

Result 10101100.00010000.01111110.00000000

What is the network address for the supplied host address? 172.16.126.0

What is the broadcast address for the supplied host address? 172.16.126.255

Is the address 172.16.101.54a Network, Host or Broadcast address? Host address

Is the address 172.16.21.255a Network, Host or Broadcast address? Broadcast address

Is the address 172.16.54.0a Network, Host or Broadcast address? Network address

Is the address 172.16.220.43a Network, Host or Broadcast address? Host address

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Subnetting Practice # 3

Host IP Address: 192.166.21.83 Five bits have been borrowed to create the required subnets.

What class is this address? Class C

What is the default subnet mask? 255.255.255.0

What is the subnet mask for this host in dotted decimal format? 255.255.255.248

What is the subnet mask for this host in IP Prefix format? /29

How many subnets were created? 32

How many hosts per subnet? 8

How many usable hosts per subnet? 6

Perform the ANDing process on the supplied

host address

Address 11000000. 10100110.00010101.01010011

Subnet Mask 11111111.11111111.11111111.11111000

Result 11000000. 10100110.00010101.01010000

What is the network address for the supplied host address? 192.166.21.80

What is the broadcast address for the supplied host address? 192.166.21.87

Is the address 192.166.21.70a Network, Host or Broadcast address? Host address

Is the address 192.166.21.135a Network, Host or Broadcast address? Broadcast address

Is the address 192.166.21.72a Network, Host or Broadcast address? Network address

Is the address 192.166.21.167a Network, Host or Broadcast address? Broadcast address

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Subnetting Practice # 4

Host IP Address: 183.91.104.16 Eleven bits have been borrowed to create the required subnets.

What class is this address? Class B

What is the default subnet mask? 255.255.0.0

What is the subnet mask for this host in dotted decimal format? 255.255.255.224

What is the subnet mask for this host in IP Prefix format? /27

How many subnets were created? 2048

How many hosts per subnet? 32

How many usable hosts per subnet? 30

Perform the ANDing process on thesupplied host address

Address 10110111.01011011.01101000.00010000

Subnet Mask 11111111.11111111.11111111.11100000

Result 10110111.01011011.01101000.00000000

What is the network address for the supplied host address? 183.91.104.0

What is the broadcast address for the supplied host address? 183.91.104.31

Is the address 183.91.128.161a Network, Host or Broadcast address? Host address

Is the address 183.91.255.192a Network, Host or Broadcast address? Network address

Is the address 181.91.95.224a Network, Host or Broadcast address? Network address

Is the address 181.91.85.63a Network, Host or Broadcast address? Broadcast address

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Subnetting Practice # 5

Network Number: 192.10.10.0

Required: 14 usable subnets14 usable hosts per subnetwork

What class is this address? Class C

What is the default subnet mask? 255.255.255.0

How many bits did you borrow? 4

What is the new subnet mask for this host in dotted decimal format? 255.255.255.240

What is the new subnet mask for this host in IP Prefix format? /28

How many subnets were created? 16

How many hosts per subnet? 16

How many usable hosts per subnet? 14

Is the address 192.10.10.95a Network, Host or Broadcast address? Broadcast address

Is the address 192.10.10.152a Network, Host or Broadcast address? Host address

Is the address 192.10.10.208a Network, Host or Broadcast address? Network address

Is the address 192.10.10.120a Network, Host or Broadcast address? Host address

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Subnetting Practice # 6

Network Number: 165.127.0.0

Required: 950 usable subnets60 usable hosts per subnetwork

What class is this address? Class B

What is the default subnet mask? 255.255.0.0

How many bits did you borrow? 10

What is the new subnet mask for this host in dotted decimal format? 255.255.255.192

What is the new subnet mask for this host in IP Prefix format? /26

How many subnets were created? 1024

How many hosts per subnet? 64

How many usable hosts per subnet? 62

Is the address 165.127.0.254a Network, Host or Broadcast address? Host address

Is the address 165.127.106.63a Network, Host or Broadcast address? Broadcast address

Is the address 165.127.224.128a Network, Host or Broadcast address? Network address

Is the address 165.127.128.224a Network, Host or Broadcast address? Host address

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Subnetting Practice # 7

Network Number: 118.0.0.0

Required: 119 usable subnets

What class is this address? Class A

What is the default subnet mask? 255.0.0.0

How many bits did you borrow? 7

What is the new subnet mask for this host in dotted decimal format? 255.254.0.0

What is the new subnet mask for this host in IP Prefix format? /15

How many subnets were created? 128

How many hosts per subnet?(Use a calculator for this one.) 131072

How many usable hosts per subnet? 131070

Is the address 118.61.255.255a Network, Host or Broadcast address? Broadcast address

Is the address 118.238.255.255a Network, Host or Broadcast address? Host address

Is the address 118.118.255.118a Network, Host or Broadcast address? Host address

Is the address 118.224.0.0a Network, Host or Broadcast address? Network address

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Subnetting Practice # 8

Network Number: 178.101.0.0

Required: 1,957 usable subnets15 usable hosts per subnet

What class is this address? Class B

What is the default subnet mask? 255.255.0.0

How many bits did you borrow? 11

What is the new subnet mask for this host in dotted decimal format? 255.255.255.224

What is the new subnet mask for this host in IP Prefix format? /27

How many subnets were created? 2048

How many hosts per subnet? 32

How many usable hosts per subnet? 30

Is the address 178.101.1.113a Network, Host or Broadcast address? Host address

Is the address 178.101.128.159a Network, Host or Broadcast address? Broadcast address

Is the address 178.101.192.224a Network, Host or Broadcast address? Network address

Is the address 178.101.15.15a Network, Host or Broadcast address? Host address

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Subnetting Practice # 9

You are the network administrator for XYZ Widgets and Stuff and are required to subnet their network according to the diagram. Your head office has assigned the network 193.5.5.0 for you to use. It is the corporate policy that the IP address assigned to a default gateway is always the first host address in the subnet and subnets are always assigned beginning with the first usable subnet in the list.

Answer the following: What class is this address? Class C What is the default subnet

mask (Dotted Decimal) 255.255.255.0

How many bits did you borrow? 3 What is the new subnet

mask (Dotted Decimal)? 255.255.255.224

How many subnets have been created? 8 What is the new subnet

mask (IP Prefix)? /27

How many hosts are there per subnet? 32 How many usable hosts

per subnet? 30

Provide the required addresses for the subnetworks you will use.

Network Network Address Host Range Broadcast Address

Sales 193.5.5.0 193.5.5.1 - 193.5.5.30 193.5.5.31

Production 193.5.5.32 193.5.5.33 - 193.5.5.62 193.5.5.63

Provide the required default gateway address assignments.

Interface IP Address Subnet Mask (Dotted Decimal)IP Address and Subnet Mask in IP Prefix Format

fa0/0 – Sales 193.5.5.1 255.255.255.224 193.5.5.1/27

fa0/1 - Production 193.5.5.33 255.255.255.224 193.5.5.33/27

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Subnetting Practice # 10

You are the network administrator for Bunch-A-Hosts Limited in Windsor and are required to subnet the network according to the diagram. You have decided to use the network 172.16.0.0. There are multiple subnets at each site but you are only responsible for providing usable subnetworks with enough IP addresses to cover the current number of hosts and future growth as outlined below.

Ottawa - 5% GrowthWindsor - 5% GrowthToronto - 5% GrowthLondon - 10% Growth

Subnetworks are assigned beginning with the first usable subnet.

Answer the following:

What class is this address? Class B What is the default subnet

mask (Dotted Decimal) 255.255.0.0

How many bits did you borrow? 6 What is the new subnet

mask (Dotted Decimal)? 255.255.252.0

How many subnets have been created? 64 What is the new subnet

mask (IP Prefix)? /22

How many hosts are there per subnet? 1024 How many usable hosts

per subnet? 1022

Provide the required addresses for the subnetworks you will use.

Network Network Address Host Range Broadcast Address

Ottawa 172.16.0.0 172.16.0.1 - 172.16.3.254 172.16.3.255

Windsor 172.16.4.0 172.16.4.1 - 172.16.7.254 172.16.7.255

Toronto 172.16.8.0 172.16.8.1 - 172.16.11.254 172.16.11.255

London 172.16.12.0 172.16.12.1 - 172.16.15.254 172.16.15.255

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Subnetting Practice # 11

You are the network administrator for Leaky Plumbing Supplies Ltd. and are required to subnet their network according to the diagram. Your head office has assigned the network 172.25.0.0 for you to use. The company anticipates a 25% growth in all areas over the next 5 years. Your boss expects you to plan for the future. It is the corporate policy that the IP address assigned to a default gateway is always the last host address in the subnet and subnets are always assigned beginning with the first usable subnet in the list.

Answer the following:

What class is this address? Class B What is the default subnet

mask (Dotted Decimal) 255.255.0.0

How many bits did you borrow? 9 What is the new subnet

mask (Dotted Decimal)? 255.255.255.128

How many subnets have been created? 512 What is the new subnet

mask (IP Prefix)? /25

How many hosts are there per subnet? 128 How many usable hosts

per subnet? 126

Provide the required addresses for the subnetworks you will use.

Network Network Address Host Range Broadcast Address

Sales 172.25.0.0 172.25.0.1 - 172.25.0.126 172.25.0.127

Marketing 172.25.0.128 172.25.0.129 - 172.25.0.254 172.25.0.255

Production 172.25.1.0 172.25.1.1- 172.25.1.126 172.25.1.127

Provide the required default gateway address assignments.

Interface IP Address Subnet Mask (Dotted Decimal)IP Address and Subnet Mask in IP Prefix Format

fa0/0 – Sales 172.25.0.126 255.255.255.128 172.25.0.126/25

fa0/1 - Marketing 172.25.0.254 255.255.255.128 172.25.0.254/25

fa1/0 - Production 172.25.1.126 255.255.255.128 172.25.1.126/25

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Subnetting Practice # 12

You are the network administrator for Mangiare Food Supplies in Rome and are required to subnet the network according to the diagram. You have decided to use the network 172.31.0.0. It is the corporate policy that the IP address assigned to a default gateway is always the last host address in the subnet and subnets are always assigned beginning with the first usable subnet in the list. WAN Links use the first two usable addresses in a subnet.

Answer the following:

What class is this address? Class B What is the default subnet

mask (Dotted Decimal) 255.255.0.0

How many bits did you borrow? 10 What is the new subnet

mask (Dotted Decimal)? 255.255.255.192

How many subnets have been created? 1024 What is the new subnet

mask (IP Prefix)? /26

How many hosts are there per subnet? 64 How many usable hosts

per subnet? 62

Provide the required addresses for the subnetworks you will use.

Network Network Address Host Range Broadcast Address

Rome - Production 172.31.0.0 172.31.0.1 - 172.31.0.62 172.31.0.63

Rome- Accounting 172.31.0.64 172.31.0.65 - 172.31.0.126 172.31.0.127

WAN Link 172.31.0.128 172.31.0.129 - 172.31.0.190 172.31.0.191

Paris - Accounting 172.31.0.192 172.31.0.193 - 172.31.0.254 172.31.0.255

Paris - Sales 172.31.1.0 172.31.1.1 - 172.31.1.62 172.31.1.63

Provide the required default gateway and WAN port address assignments.

Interface IP Address Subnet Mask (Dotted Decimal)IP Address and Subnet Mask in IP Prefix Format

Rome – fa0/0 172.31.0.62 255.255.255.192 172.31.0.62/26

Rome – fa0/1 172.31.0.126 255.255.255.192 172.31.0.126/26

Rome – s0/2/0 172.31.0.129 255.255.255.192 172.31.0.190/26

Paris – s0/2/0 172.31.0.130 255.255.255.192 172.31.0.130/26

Paris – fa0/1 172.31.0.254 255.255.255.192 172.31.0.254/26

Paris – fa0/0 172.31.1.62 255.255.255.192 172.31.1.62/26

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