Mastering Subnetting for Cisco CCNA Success

What should be done to the subnet mask if the IP address of Workstation A is 192.0.10.24/28 and Workstation B is 192.0.10.100/28 to allow for communications?

• A. Change the subnet mask of the hosts to /25.
• B. Keep the current subnet mask.
• C. Change the subnet mask to /27.
• D. Change the subnet mask of the hosts to /24.

Answer: (A)

To establish communication between Workstation A (192.0.10.24/28) and Workstation B (192.0.10.100/28), the subnet mask needs to be adjusted since both workstations currently reside in different subnets due to the /28 subnetting. The /28 subnet mask allows for 16 IP addresses (from .0 to .15, .16 to .31, etc.), which means each subnet can contain a maximum of 14 usable hosts (since 2 are reserved for the network and broadcast addresses). In this case, Workstation A is in the subnet 192.0.10.16 (network address) to 192.0.10.31 (broadcast address), while Workstation B is in the subnet 192.0.10.96 (network address) to 192.0.10.111 (broadcast address). They belong to entirely separate subnets, preventing communication. By changing the subnet mask to /25, the network is expanded to cover a range of 128 IP addresses (from .0 to .127). This change means that both Workstation A and Workstation B would fall within the same network, allowing them to communicate with each other. This

Understanding how subnetting works is crucial for anyone preparing for the Cisco Certified Network Associate (CCNA) exam. You know, it’s like solving a puzzle; one piece out of place can affect the entire picture, and in networking, that piece is often the subnet mask. So, let’s dive into it.

Imagine you have two workstations trying to communicate – Workstation A with an IP address of 192.0.10.24/28 and Workstation B with 192.0.10.100/28. At first glance, they both seem well-equipped to chat, right? I mean, they have their unique addresses set up already. But here’s the kicker: they can’t communicate due to their subnet configuration. Surprised? Let’s break it down.

Wait, What’s This About Subnets?

Alright, so let’s take a quick detour into subnetting basics. When you use a subnet mask like /28, it means you’re breaking down the network into smaller parts. In this case, a /28 subnet can accommodate 16 IP addresses. Sound small? Maybe, but here’s the catch – only 14 can actually be used by devices (the other two are reserved for the network and broadcast addresses).

So, in our current scenario:

• Workstation A (192.0.10.24) is in the range of 192.0.10.16 to 192.0.10.31.

• Workstation B (192.0.10.100) is in a different range – from 192.0.10.96 to 192.0.10.111.

Because they each belong to distinctly different subnets, they can't communicate. They’re like two neighbors who can’t find common ground to chat – frustrating, isn't it?

So, What’s the Fix?

Now that we’ve unpacked the problem, how do we solve it? The answer lies in adjusting the subnet mask. To allow both workstations to communicate, we need to change the subnet mask from /28 to /25. By doing this, we’d expand our network to cover the range of 128 IP addresses (from 192.0.10.0 to 192.0.10.127).

This adjustment combines both workstations within the same subnet, breaking down walls and enabling smooth communication. Picture it like merging two villages into one town. Suddenly, your neighbors (or in this case, the workstations) can talk freely!

Why Does This Matter for CCNA?

Many students prepping for the CCNA exam underestimate the importance of understanding subnetting. It’s not just theoretical fluff; it's essential for real-world networking. Whether you’re configuring routers or troubleshooting communication issues, knowing how to adjust subnet masks will carry you far. Plus, let’s be honest—who doesn’t want to ace that exam, right?

Wrapping Up: Get Comfortable with Subnetting

So, if you’ve got your sights set on the CCNA, understanding subnetting is a non-negotiable part of your study plan. This isn’t just about memorizing configurations; it’s about comprehending how these concepts work together to form the backbone of effective network communication.

Don't shy away from diving into different scenarios and practice problems. The more you engage with these concepts, the clearer they will become. Embrace the journey, have fun with it, and soon you'll be subnetting like a seasoned pro!