How can I check if an ip is in a network in Python?

In Python, to verify if an IP address belongs to a specific network, we can utilize the ipaddress module, which is part of Python's standard library and is designed for handling IPv4 and IPv6 addresses and networks.

Below is a step-by-step approach to determine whether an IP address falls within a designated network:

Step 1: Import the ipaddress module

python
import ipaddress

Step 2: Use ipaddress.ip_network() to define the network

This function allows you to define a network. For instance, if the network is 192.168.1.0/24:

python
network = ipaddress.ip_network('192.168.1.0/24')

Step 3: Use ipaddress.ip_address() to define the IP address to check

Similarly, define the IP address:

python
ip = ipaddress.ip_address('192.168.1.10')

Step 4: Use the in keyword to check if the IP is within the network

Finally, employ the in keyword to verify if the IP is contained within the previously defined network:

python
if ip in network:
    print("IP address is in the network")
else:
    print("IP address is not in the network")

Complete Example

By combining the above steps, here is a full code example:

python
import ipaddress

# Define the network
network = ipaddress.ip_network('192.168.1.0/24')

# Define the IP address
ip = ipaddress.ip_address('192.168.1.10')

# Check if the IP is in the network
if ip in network:
    print("IP address is in the network")
else:
    print("IP address is not in the network")

This example illustrates how to check if the IP address 192.168.1.10 is within the network 192.168.1.0/24. Executing this code will output 'IP address is in the network'. If you modify the IP address or network, the output may differ based on whether the IP address genuinely resides within the network.

This method is applicable to both IPv4 and IPv6 addresses; simply adjust the IP address and network parameters accordingly.