To limit the number of guests per subnet to a maximum of 14 in a private cloud test environment, which service should the administrator use?

The most suitable service for limiting the number of guests per subnet to a maximum of 14 is DHCP (Dynamic Host Configuration Protocol). DHCP is responsible for dynamically assigning IP addresses to devices on a network. If an administrator wants to constrain the number of devices that can connect to a specific subnet, they can configure DHCP to limit the lease pool to 14 IP addresses.

While subnets themselves can be designed to accommodate a certain number of addresses, the administrator must ensure the network is set up correctly with a subnet mask that allows for 14 usable IP addresses. However, DHCP plays a more active role in enforcing limits by controlling how many IP addresses can be issued on that subnet during its operation. This dynamic allocation approach is more efficient in managing the guest count.

Using VLANs can help in segmenting network traffic but doesn't inherently limit the number of hosts on a subnet. Similarly, a gateway serves as an access point to route traffic between different networks but does not manage the number of hosts in a given subnet by itself. Therefore, DHCP stands out as the service specifically tailored for managing and limiting the number of usable addresses each subnet can utilize effectively.