200-301 Question 87
Single answerA network administrator needs to configure the IP address and subnet mask for a router interface. The network uses the 192.168.10.0/24 subnet, and the router interface must be assigned the first valid host address. Which of the following configurations should the administrator apply to the router interface?
- A
IP address: 192.168.10.0, Subnet mask: 255.255.255.0
- B
IP address: 192.168.10.1, Subnet mask: 255.255.255.0
- C
IP address: 192.168.10.255, Subnet mask: 255.255.255.0
- D
IP address: 192.168.10.128, Subnet mask: 255.255.255.0
Show answer and explanation
Correct answer: B
Explanation
In a /24 subnet, the network address is the first address in the range (192.168.10.0), and the broadcast address is the last address in the range (192.168.10.255). The first valid host address is 192.168.10.1. When configuring the router interface, the administrator must assign it a valid host address within the subnet, and 192.168.10.1 is the correct answer for this scenario.
- A. Incorrect.
192.168.10.0 is the network ID for the subnet and cannot be assigned to a device as a usable host address.
- B. Correct.
192.168.10.1 is the first valid host address within the 192.168.10.0/24 subnet, making it the correct configuration for the router interface.
- C. Incorrect.
192.168.10.255 is the broadcast address for the subnet and cannot be assigned to a device as a usable host address.
- D. Incorrect.
192.168.10.128 is a valid host address but is not the first valid host address in the 192.168.10.0/24 subnet.