In this setup, there are four devices connected to a network, and the goal is to establish communication between specific hosts.

1. Host A (My PC) is connected to Interface A1, and it needs to communicate with Host B (My Little Brother's Computer), which is connected to Interface B1. Currently, the connection is failing because their IP configurations are not compatible or not in the same subnet.
2. Host C (My Mac) is connected to Interface C1, and it needs to communicate with Host D (My Little Sister's Computer), which is connected to Interface D1. However, the connection is also failing because the IP settings for Host D are incomplete, and the devices are not configured to be in the same subnet.

Each interface has an assigned subnet mask (e.g., 255.255.255.0) that determines the range of valid IP addresses in the network. The task is to configure the IP addresses and subnet masks for the interfaces so that communication between the respective hosts is successful.

What is an Interface?

An interface is a point of connection on a device that allows it to send and receive data on a network. Think of it as a "port" through which the device communicates with other devices. Each interface needs:

• An IP address: This is the unique identifier of the device on the network.
• A subnet mask: This determines which IP addresses are part of the same network.

In this setup:

• Interface A1 is the connection point for Host A (My PC).
• Interface B1 is the connection point for Host B (My Little Brother's Computer).
• Interface C1 is the connection point for Host C (My Mac).
• Interface D1 is the connection point for Host D (My Little Sister's Computer).

How are the Devices Connected?

• Host A (My PC) is connected to Host B (My Little Brother's Computer) via Interfaces A1 and B1.