Intermediate Security Groups

Allow connections by IP address

To specify a single IP address or a range of IP addresses for a security group rule, you would choose CIDR for the Remote option.

CIDR (or Classless inter-domain routing) notation is a method of representation of IP addresses. It is made up of two parts, the first being an IP address, followed by a slash (/) and a number indicating how many bits of the address are used to define the network.

Some common options might be:

  • To allow access to any available IP address. This is potentially risky and should generally be avoided if possible.
  • To allow any IP address between and
  • To allow the single IP address The /32 component is used for identifying a single IPv4 address.