220-1101 Question 143
Single answerIPv4A technician is configuring a small office printer with a static IPv4 address so employees on the local network can always find it at the same address. The office router uses the 192.168.10.0/24 network and hands out DHCP addresses from 192.168.10.100 through 192.168.10.200. Which of the following IPv4 settings is the BEST choice for the printer to avoid an address conflict while allowing communication on the local network and internet?
- A
IP address 192.168.10.50, subnet mask 255.255.255.0, default gateway 192.168.10.1
- B
IP address 192.168.10.150, subnet mask 255.255.255.0, default gateway 192.168.10.1
- C
IP address 192.168.11.50, subnet mask 255.255.255.0, default gateway 192.168.10.1
- D
IP address 192.168.10.255, subnet mask 255.255.255.0, default gateway 192.168.10.1
Show answer and explanation
Correct answer: A
Explanation
In a 192.168.10.0/24 network, valid host addresses range from 192.168.10.1 to 192.168.10.254, excluding any addresses reserved for infrastructure or DHCP allocation. Because the router is already using 192.168.10.1 and DHCP leases 192.168.10.100 through 192.168.10.200, the best practice is to assign a static address outside the DHCP pool but still within the same subnet, such as 192.168.10.50. This reduces the risk of duplicate IP conflicts. In IPv4, the network address for this subnet is 192.168.10.0 and the broadcast address is 192.168.10.255, so neither can be assigned to a host. These practices align with common TCP/IP configuration guidance and standard subnetting behavior used in enterprise and small office networks.
- A. Correct.
Correct. 192.168.10.50 is in the same 192.168.10.0/24 subnet as the router and other hosts, but it is outside the DHCP scope of 192.168.10.100-192.168.10.200. That makes it an appropriate static address choice in this scenario. The subnet mask 255.255.255.0 matches the /24 network, and the default gateway 192.168.10.1 is a valid router address for off-network communication such as internet access.
- B. Incorrect.
Incorrect. Although 192.168.10.150 is in the correct subnet and uses the proper subnet mask and gateway, it falls inside the DHCP pool. Assigning a static address from within the DHCP scope can create an IP conflict if the DHCP server later leases the same address to another device. This is a common real-world mistake when manually configuring printers or servers.
- C. Incorrect.
Incorrect. 192.168.11.50 is not in the same subnet as the 192.168.10.0/24 network when using a 255.255.255.0 mask. A device with this address would treat 192.168.10.1 as being on a different network, so communication would fail without routing configured for that subnet. Someone might choose this option because it looks similar, but changing the third octet places the host on a different network.
- D. Incorrect.
Incorrect. 192.168.10.255 is the broadcast address for the 192.168.10.0/24 network and cannot be assigned to a host. Broadcast addresses are reserved for sending traffic to all devices on the subnet. This option tests a common IPv4 addressing error involving network, host, and broadcast address ranges.