A group of services connected to IP addresses known as IP services make it possible to communicate within an Azure Virtual Network. Azure uses both public and private IP addresses for resource communication. Both the public Internet and a private Azure Virtual Network can be used for resource communication.
IP services consist of:
- Public IP addresses
- Public IP address prefixes
- Private IP addresses
- Routing preference
- Routing preference unmetered
Public IP addresses
Internet resources communicate with resources in Azure using public IP addresses. An IPv4 or IPv6 address can be used to create public IP addresses. A dual-stack setup with an IPv4 and IPv6 address might be available to you. Standard and Basic SKUs are both available for public IP addresses. Public IP addresses may be assigned either statically or dynamically.
Public IP addresses are resources with unique characteristics. The following resources can be linked to a public IP address:
- Virtual machine network interfaces
- Internet-facing load balancers
- Virtual Network gateways (VPN/ER)
- NAT gateways
- Application gateways
- Azure Firewall
- Bastion Host
Public IP address prefixes
In Azure, public IP prefixes are set aside IP address blocks. Prefixes for public IP addresses might be IPv4 or IPv6. Public IP address prefixes in regions with availability zones can be created as zone-redundant or linked to a particular availability zone. You can create public IP addresses after creating the public IP prefix.
The following public IP prefix sizes are available:
- /28 (IPv4) or /124 (IPv6) = 16 addresses
- /29 (IPv4) or /125 (IPv6) = 8 addresses
- /30 (IPv4) or /126 (IPv6) = 4 addresses
- /31 (IPv4) or /127 (IPv6) = 2 addresses
A Classless Inter-Domain Routing (CIDR) mask size is used to specify the prefix size.
The number of prefixes that can be produced inside a subscription is unrestricted. More static public IP addresses than permitted by your subscription cannot be generated in ranges.
Private IP addresses
Azure resources can communicate with one another thanks to private IPs. Resources on Azure are given private IP addresses from the virtual network subnet where they are located. In Azure, private IP addresses are either assigned statically or randomly.
A private IP address can be connected to a variety of resources, including:
- Virtual machines
- Internal load balancers
- Application gateways
- Private endpoints