Refer to the diagram.
All hosts have connectivity with one another. Which statements describe the addressing scheme
that is in use in the network? (Choose three.)
A.
The subnet mask in use is 255.255.255.192.
B.
The subnet mask in use is 255.255.255.128.
C.
The IP address 172.16.1.25 can be assigned to hosts in VLAN1
D.
The IP address 172.16.1.205 can be assigned to hosts in VLAN1
E.
The LAN interface of the router is configured with one IP address.
F.
The LAN interface of the router is configured with multiple IP addresses.
Explanation
First we should notice that different VLANs must use different sub-networks. In this case Host A (172.16.1.126) and Host B (172.16.1.129) are in different VLANs and must use different sub-networks. Therefore the subnet mask in use here should be 255.255.255.128. In particular, it is 172.16.1.0/25 with 2 sub-networks:
+ Sub-network 1: 172.16.1.0 -> 172.16.1.127 (assigned to VLAN 1)
+ Sub-network 2: 172.16.1.128 -> 172.16.1.255 (assigned to VLAN 2)
-> B is correct.
The IP address 172.16.1.25, which is in the same sub-network with host A so it can be assigned to VLAN 1 -> C is correct.
To make different VLANs communicate with each other we can configure sub-interfaces (with a different IP address on each interface) on the LAN interface of the router -> F is correct.
Wouldn’t mask of 255.255.255.192 works here as well? Networks would be:
0 (hosts 1-62)
64 (hosts 65-126)
128 (hosts 129-191)
VLAN1 and VLAN2 would still need a router for their gateways. Hosts A and B are the first or last available hosts in their networks. Host 172.16.1.25 would still reside in VLAN1…
Mammoth the question says there is 114 hosts in VLAN 2. therefore 192 is the right mask.