Subnets in the VPC Flashcards
True or false: AWS automatically create a Virtual Private Cloud (VPC) for each account.
True.
What are the default Virtual Private Cloud (VPC) subnets?
The default VPC includes six subnets pre-configured by AWS with each subnet residing in a different availability zone, giving high availability to resources within the VPC.
What does 172.31.0.0 indicate?
The first 16 bits (172 and 31) are fixed for network identification and the remaining 16 bits are available for subnets and hosts within those subnets.
How do you create additional subnets?
IPv4 Subnetting, which takes a large range (like 172.31.0.0/16) and subdivides it into smaller chunks for different use cases, such as isolating resources or limiting the number of hosts in a subnet.
What is a subnet mask?
A 32-bit number used to divide an IP address into network and host proportions.
What is a network prefix?
A network prefix specifies the portion of the address used to identify the network itself, while the remaining bits identify hosts within that network.
Given 172.31.0.0/20, which bits are used for the network, which are the host bits and how many possible host addresses can be created.
1) 20 bits are used for the network.
2) Subtract the network bits from 32 to calculate the host bits. 32 - 20 = 12 bits for hosts.
3) 2 ^ 12 = 4096 possible host addresses in the subnet.
How do you calculate address space in subnets?
Subtract the prefix length from 32 to find the host bits.
Calculate the number of possible addresses by raising 2 to the power of the number of host bits.
