What Tunnel Network was configured for the OpenVPN server?

• A. 198.28.56.0/24
• B. 198.28.20.0/16
• C. 198.168.20.0/24
• D. 198.28.20.0/24

Answer: (D)

The tunnel network is the virtual IP space OpenVPN uses to assign addresses to all connected clients and to route traffic through the VPN. It should be a dedicated, non-overlapping range chosen for the VPN so client addresses don’t collide with real networks.

In this setup, the tunnel network is 198.28.20.0/24. That means the VPN will treat 198.28.20.0 as the network address, 198.28.20.255 as the broadcast, and assign individual client IPs from 198.28.20.1 through 198.28.20.254. This /24 is a sensible, compact range commonly used for VPN tunnels and does not intrude on other networks.

Why the other options aren’t the best fit: a /24 starting at 198.28.56.0 would designate a different VPN network, which isn’t the one configured here; a /16 would allocate a much larger space (over 65,000 addresses) and is unusual for a tunnel network, risking overlaps with other networks; 198.168.20.0/24 uses a different first octet, misaligning with the lab’s addressing plan.