# 7.1.4.9 Lab – Identifying IPv4 Addresses Answers

## Lab– Identifying IPv4 Addresses (Answers Version – Optional Lab)

Answers Note: Red font color or gray highlights indicate text that appears in the instructor copy only. Optional activities are designed to enhance understanding and/or to provide additional practice.

### Objectives

Part 1: Identify IPv4 Addresses

Part 2: Classify IPv4 Addresses

### Background / Scenario

In this lab, you will examine the structure of Internet Protocol version 4 (IPv4) addresses. You will identify the various types of IPv4 addresses and the components that help comprise the address, such as network portion, host portion, and subnet mask. Types of addresses covered include public, private, unicast, and multicast.

Answers Note: This optional activity can be done individually in class or assigned as homework. The lab can also be done in class with students working in pairs. If the lab is done in class, it should be followed up by discussion with correct answers. All public IP addresses used in this lab are owned by Cisco.

### Required Resources

• Device with Internet access
• Optional: IPv4 address calculator

### Part 1: Identify IPv4 Addresses

Step 1: In Part 1, you will be given several examples of IPv4 addresses and will complete tables with appropriate information.

#### Step 1: Analyze the table shown below and identify the network portion and host portion of the given IPv4 addresses.

The first two rows show examples of how the table should be completed.

Key for table:

N = all 8 bits for an octet are in the network portion of the address

n = a bit in the network portion of the address

H = all 8 bits for an octet are in the host portion of the address

h = a bit in the host portion of the address

 IP Address/Prefix Network/Host N,n = Network, H,h = Host Subnet Mask Network Address 192.168.10.10/24 N.N.N.H 255.255.255.0 192.168.10.0 10.101.99.17/23 N.N.nnnnnnnh.H 255.255.254.0 10.101.98.0 209.165.200.227/27 N.N.N.nnnhhhhh 255.255.255.224 209.165.200.224 172.31.45.252/24 N.N.N.H 255.255.255.0 172.31.45.0 10.1.8.200/26 N.N.N.nnhhhhhh 255.255.255.192 10.1.8.192 172.16.117.77/20 N.N.nnnnhhhh.H 255.255.240.0 172.16.112.0 10.1.1.101/25 N.N.N.nhhhhhhh 255.255.255.128 10.1.1.0 209.165.202.140/27 N.N.N.nnnhhhhh 255.255.255.224 209.165.202.128 192.168.28.45/28 N.N.N.nnnnhhhh 255.255.255.240 192.168.28.32

#### Step 2: Analyze the table below and list the range of host and broadcast addresses given a network/prefix mask pair.

The first row shows an example of how the table should be completed.

 IP Address/Prefix First Host Address Last Host Address Broadcast Address 192.168.10.10/24 192.168.10.1 192.168.10.254 192.168.10.255 10.101.99.17/23 10.101.98.1 10.101.99.254 10.101.99.255 209.165.200.227/27 209.165.200.225 209.165.200.254 209.165.200.255 172.31.45.252/24 172.31.45.1 172.31.45.254 172.31.45.255 10.1.8.200/26 10.1.8.193 10.1.8.254 10.1.8.255 172.16.117.77/20 172.16.112.1 172.16.127.254 172.16.127.255 10.1.1.101/25 10.1.1.1 10.1.1.126 10.1.1.127 209.165.202.140/27 209.165.202.129 209.165.202.158 209.165.202.159 192.168.28.45/28 192.168.28.33 192.168.28.46 192.168.28.47

### Part 2: Classify IPv4 Addresses

In Part 2, you will identify and classify several examples of IPv4 addresses.

#### Step 1: Analyze the table shown below and identify the type of address (network, host, multicast, or broadcast address).

The first row shows an example of how the table should be completed.

 IP Address Subnet Mask Address Type 10.1.1.1 255.255.255.252 host 192.168.33.63 255.255.255.192 broadcast 239.192.1.100 255.252.0.0 multicast 172.25.12.52 255.255.255.0 host 10.255.0.0 255.0.0.0 host 172.16.128.48 255.255.255.240 network 209.165.202.159 255.255.255.224 broadcast 172.16.0.255 255.255.0.0 host 224.10.1.11 255.255.255.0 multicast

#### Step 2: Analyze the table shown below and identify the address as public or private.

 IP Address/Prefix Public or Private 209.165.201.30/27 Public 192.168.255.253/24 Private 10.100.11.103/16 Private 172.30.1.100/28 Private 192.31.7.11/24 Public 172.20.18.150/22 Private 128.107.10.1/16 Public 192.135.250.10/24 Public 64.104.0.11/16 Public

#### Step 3: Analyze the table shown below and identify whether the address/prefix pair is a valid host address.

 IP Address/Prefix Valid Host Address? Reason 127.1.0.10/24 No Loopback 172.16.255.0/16 Yes Host address 241.19.10.100/24 No Reserved 192.168.0.254/24 Yes Host address 192.31.7.255/24 No Broadcast 64.102.255.255/14 Yes Host address 224.0.0.5/16 No Multicast 10.0.255.255/8 Yes Host address 198.133.219.8/24 Yes Host address

### Reflection

Why should we continue to study and learn about IPv4 addressing if the available IPv4 address space is depleted?

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Many organizations will continue to use the private IPv4 address space for their internal networking needs. The public IPv4 addresses will be used for many years to come.