.Which is the valid broadcast ID for the IP address 188.8.131.52 with a subnet mask of 255.255.255.128?
Correct Answer: A
184.108.40.206 is the valid broadcast ID for the IP address 220.127.116.11 with a subnet mask of 255.255.255.128. The valid range for the IP address 18.104.22.168 with a subnet
mask of 255.255.255.128 is 22.214.171.124 – 126.96.36.199. The subnet ID is 188.8.131.52.
Subnetting allows you to split single and large subnets defined by Class A, B, and C IP addresses into multiple subnets with smaller IP address host ranges. Subnetting allows efficient
use of IP addressing space, which has become a scarce resource.
To subnet an existing network, you will use host bits to split the IP address into multiple logical subnets. For example, if you use three bits of the host ID for subnetting, you have
created 23 = 2 x 2 x 2 = 8 subnets. Remaining bits of the host ID in decimal form will form the number of hosts on each subnet.
All other options are incorrect as these IP addresses fall in other subnets.
184.108.40.206 is the network ID for the next subnet created when using a mask of 255.255.255.128 on the class C network 220.127.116.11. The following network IDs are created
when you use a mask of 255.255.255.128 on the class C network 18.104.22.168:
22.214.171.124 – Valid range 126.96.36.199-188.8.131.52, 184.108.40.206 is the broadcast
220.127.116.11 – valid range 18.104.22.168-22.214.171.124, 126.96.36.199 is the broadcast
188.8.131.52 and 184.108.40.206 are both valid addresses in the second subnet created, that is, the 220.127.116.11 network.
Configure, verify, and troubleshoot IPv4 addressing and subnetting
Cisco > Technology Support > IP > IP Routing > Design Technotes > IP Addressing and Subnetting for New Users > Document ID: 13788 > Understanding IP Addresses