CompTIA Cloud+ Practice Test

What determines the size of a group of servers in the same subnet?

1. Default gateway

2. DNS

3. NTP

4. CIDR block

The correct answer is: CIDR block

The size of a group of servers in the same subnet is determined by the CIDR (Classless Inter-Domain Routing) block. CIDR is a method for allocating IP addresses and routing Internet Protocol packets more efficiently. It allows for a flexible allocation of IP address ranges, which means that network administrators can specify how many addresses are included within a subnet. A CIDR block is represented with a notation that specifies the number of bits used for the network part of the address, which defines the size of the subnet. For example, a CIDR block of /24 indicates that the first 24 bits of the address are used for the network ID, leaving the remaining 8 bits available for host addresses. This results in 256 possible IP addresses within that subnet, with some reserved for network and broadcast addresses. In contrast, the other options serve different purposes: - The default gateway is the device that routes traffic from a local network to destinations outside the network, but it does not determine the size of the subnet itself. - DNS (Domain Name System) is responsible for resolving human-readable domain names to IP addresses, which is essential for network communication but does not influence the size of the subnet. - NTP (Network Time Protocol) is used