Merge pull request #218665 from asudbring/ip-concepts-freshness

Freshness update to public IP address conceptual information article

Author: Court72

articles/virtual-network/ip-services/public-ip-addresses.md

@@ -7,40 +7,50 @@ author: asudbring
 ms.service: virtual-network
 ms.subservice: ip-services
 ms.topic: conceptual
-ms.date: 12/27/2021
+ms.date: 11/16/2022
 ms.author: allensu
 ---
 
 # Public IP addresses
 
 Public IP addresses allow Internet resources to communicate inbound to Azure resources. Public IP addresses enable Azure resources to communicate to Internet and public-facing Azure services. The address is dedicated to the resource, until it's unassigned by you. A resource without a public IP assigned can communicate outbound. Azure dynamically assigns an available IP address that isn't dedicated to the resource. For more information about outbound connections in Azure, see [Understand outbound connections](../../load-balancer/load-balancer-outbound-connections.md?toc=%2fazure%2fvirtual-network%2ftoc.json).
 
-In Azure Resource Manager, a [public IP](virtual-network-public-ip-address.md) address is a resource that has its own properties. Some of the resources you can associate a public IP address resource with:
+In Azure Resource Manager, a [public IP](virtual-network-public-ip-address.md) address is a resource that has its own properties. 
+
+The following resources can be associated with a public IP address:
 
 * Virtual machine network interfaces
-* Virtual machine scale sets
+
+* Virtual Machine Scale Sets
+
 * Public Load Balancers
+
 * Virtual Network Gateways (VPN/ER)
+
 * NAT gateways
+
 * Application Gateways
+
 * Azure Firewall
+
 * Bastion Host
+
 * Route Server
 
 For Virtual Machine Scale Sets, use [Public IP Prefixes](public-ip-address-prefix.md).
 
 ## At-a-glance
 
-The following table shows the property a public IP can be associated to a resource and the allocation methods. Note that public IPv6 support isn't available for all resource types at this time.
+The following table shows the property a public IP can be associated to a resource and the allocation methods. Public IPv6 support isn't available for all resource types at this time.
 
 | Top-level resource | IP Address association | Dynamic IPv4 | Static IPv4 | Dynamic IPv6 | Static IPv6 |
 | --- | --- | --- | --- | --- | --- |
 | Virtual machine |Network interface |Yes | Yes | Yes | Yes |
-| Public Load balancer |Front-end configuration |Yes | Yes | Yes |Yes |
-| Virtual Network gateway (VPN) |Gateway IP configuration |Yes (non-AZ only) |Yes | No |No |
-| Virtual Network gateway (ER) |Gateway IP configuration |Yes | No | Yes (preview) |No |
+| Public Load Balancer |Front-end configuration |Yes | Yes | Yes |Yes |
+| Virtual Network Gateway (VPN) |Gateway IP configuration |Yes (non-AZ only) |Yes | No |No |
+| Virtual Network Gateway (ER) |Gateway IP configuration |Yes | No | Yes (preview) |No |
 | NAT gateway |Gateway IP configuration |No |Yes | No |No |
-| Application gateway |Front-end configuration |Yes (V1 only) |Yes (V2 only) | No | No |
+| Application Gateway |Front-end configuration |Yes (V1 only) |Yes (V2 only) | No | No |
 | Azure Firewall | Front-end configuration | No | Yes | No | No |
 | Bastion Host | Public IP configuration | No | Yes | No | No |
 | Route Server | Front-end configuration | No | Yes | No | No |
@@ -66,24 +76,32 @@ Public IP addresses are created with one of the following SKUs:
 > Basic SKU IPv4 addresses can be upgraded after creation to Standard SKU.  To learn about SKU upgrade, refer to [Public IP upgrade](public-ip-upgrade-portal.md).
 
 >[!IMPORTANT]
-> Matching SKUs are required for Load Balancer and Public IP resources. You can't have a mixture of Basic SKU resources and standard SKU resources. You can't attach standalone virtual machines, virtual machines in an availability set resource, or a virtual machine scale set resources to both SKUs simultaneously.  New designs should consider using Standard SKU resources.  Please review [Standard Load Balancer](../../load-balancer/load-balancer-overview.md?toc=%2fazure%2fvirtual-network%2ftoc.json) for details.
+> Matching SKUs are required for load balancer and public IP resources. You can't have a mixture of basic SKU resources and standard SKU resources. You can't attach standalone virtual machines, virtual machines in an availability set resource, or a virtual machine scale set resources to both SKUs simultaneously.  New designs should consider using Standard SKU resources. For more information about a standard load balancer, see [Standard Load Balancer](../../load-balancer/load-balancer-overview.md?toc=%2fazure%2fvirtual-network%2ftoc.json).
 
 ## IP address assignment
 
 Public IPs have two types of assignments:
+
 - **Static** - The resource is assigned an IP address at the time it's created. The IP address is released when the resource is deleted. 
-- **Dynamic** - The IP address *isn't* given to the resource at the time of creation when selecting dynamic.  The IP is assigned when you associate the public IP address with a resource. The IP address is released when you stop, or delete the resource
+
+- **Dynamic** - The IP address **isn't** given to the resource at the time of creation when selecting dynamic.  The IP is assigned when you associate the public IP address with a resource. The IP address is released when you stop, or delete the resource.
 
 **Static public IP addresses** are commonly used in the following scenarios:
+
 * When you must update firewall rules to communicate with your Azure resources.
+
 * DNS name resolution, where a change in IP address would require updating A records.
+
 * Your Azure resources communicate with other apps or services that use an IP address-based security model.
+
 * You use TLS/SSL certificates linked to an IP address.
 
 > [!NOTE]
 > Even when you set the allocation method to **static**, you cannot specify the actual IP address assigned to the public IP address resource. Azure assigns the IP address from a pool of available IP addresses in the Azure location the resource is created in.
 
-**Basic public IP addresses** are commonly used for when there is no dependency on the IP address. For example, a public IP resource is released from a resource named **Resource A**. **Resource A** receives a different IP on start-up if the public IP resource is reassigned. Any associated IP address is released if the allocation method is changed from **static** to **dynamic**. Any associated IP address is unchanged if the allocation method is changed from **dynamic** to **static**. Set the allocation method to **static** to ensure the IP address remains the same.
+**Basic public IP addresses** are commonly used for when there's no dependency on the IP address. 
+
+For example, a public IP resource is released from a resource named **Resource A**. **Resource A** receives a different IP on start-up if the public IP resource is reassigned. Any associated IP address is released if the allocation method is changed from **static** to **dynamic**. Any associated IP address is unchanged if the allocation method is changed from **dynamic** to **static**. Set the allocation method to **static** to ensure the IP address remains the same.
 
 | Resource | Static  | Dynamic |
 | --- | --- | --- |
@@ -94,62 +112,78 @@ Public IPs have two types of assignments:
 
 ## DNS Name Label
 
-Select this option to specify a DNS label for a public IP resource. This functionality works for both IPv4 addresses (32-bit A records) and IPv6 addresses (128-bit AAAA records).  This selection creates a mapping for **domainnamelabel**.**location**.cloudapp.azure.com to the public IP in the Azure-managed DNS. 
+Select this option to specify a DNS label for a public IP resource. This functionality works for both IPv4 addresses (32-bit A records) and IPv6 addresses (128-bit AAAA records). This selection creates a mapping for **domainnamelabel**.**location**.cloudapp.azure.com to the public IP in the Azure-managed DNS. 
 
-For instance, creation of a public IP with:
+For instance, creation of a public IP with the following settings:
 
 * **contoso** as a **domainnamelabel**
+
 * **West US** Azure **location**
 
 The fully qualified domain name (FQDN) **contoso.westus.cloudapp.azure.com** resolves to the public IP address of the resource.
 
 > [!IMPORTANT]
 > Each domain name label created must be unique within its Azure location.  
 
-If a custom domain is desired for services that use a Public IP, you can use [Azure DNS](../../dns/dns-custom-domain.md?toc=%2fazure%2fvirtual-network%2ftoc.json#public-ip-address) or an external DNS provider for your DNS Record.
+If a custom domain is desired for services that use a public IP, you can use [Azure DNS](../../dns/dns-custom-domain.md?toc=%2fazure%2fvirtual-network%2ftoc.json#public-ip-address) or an external DNS provider for your DNS Record.
 
 ## Availability Zone
 
-Public IP addresses with a Standard SKU can be created as non-zonal, zonal, or zone-redundant in [regions that support availability zones](../../availability-zones/az-region.md). A zone-redundant IP is created in all zones for a region and can survive any single zone failure.  A zonal IP is tied to a specific availability zone, and shares fate with the health of the zone. A "non-zonal" public IP addresses is placed into a zone for you by Azure and does not give a guarantee of redundancy.
+Public IP addresses with a standard SKU can be created as non-zonal, zonal, or zone-redundant in [regions that support availability zones](../../availability-zones/az-region.md). 
+
+A zone-redundant IP is created in all zones for a region and can survive any single zone failure. A zonal IP is tied to a specific availability zone, and shares fate with the health of the zone. A "non-zonal" public IP addresses are placed into a zone for you by Azure and doesn't give a guarantee of redundancy.
 
 In regions without availability zones, all public IP addresses are created as non-zonal. Public IP addresses created in a region that is later upgraded to have availability zones remain non-zonal.
 
 > [!NOTE]
-> All Basic SKU public IP addresses are created as non-zonal.  Any IP that is upgraded from a Basic SKU to Standard SKU remains non-zonal.
+> All basic SKU public IP addresses are created as non-zonal.  Any IP that is upgraded from a basic SKU to standard SKU remains non-zonal.
 
 ## Other public IP address features
 
 There are other attributes that can be used for a public IP address.  
 
 * The Global **Tier** allows a public IP address to be used with cross-region load balancers. 
+
 * The Internet **Routing Preference** option minimizes the time that traffic spends on the Microsoft network, lowering the egress data transfer cost.
 
 > [!NOTE]
-> At this time, both the **Tier** and **Routing Preference** feature are available for standard SKU IPv4 addresses only.  They also cannot be utilized on the same IP address concurrently.
+> At this time, both the **Tier** and **Routing Preference** feature are available for standard SKU IPv4 addresses only. They can't be utilized on the same IP address concurrently.
 >
 
 [!INCLUDE [ephemeral-ip-note.md](../../../includes/ephemeral-ip-note.md)]
 
 ## Limits 
 
-The limits for IP addressing are listed in the full set of [limits for networking](../../azure-resource-manager/management/azure-subscription-service-limits.md?toc=%2fazure%2fvirtual-network%2ftoc.json#networking-limits) in Azure. The limits are per region and per subscription. [Contact support](https://portal.azure.com/#blade/Microsoft_Azure_Support/HelpAndSupportBlade) to increase above the default limits based on your business needs.
+The limits for IP addressing are listed in the full set of [limits for networking](../../azure-resource-manager/management/azure-subscription-service-limits.md?toc=%2fazure%2fvirtual-network%2ftoc.json#networking-limits) in Azure. The limits are per region and per subscription. 
+
+[Contact support](https://portal.azure.com/#blade/Microsoft_Azure_Support/HelpAndSupportBlade) to increase above the default limits based on your business needs.
 
 ## Pricing
 
-Public IPv4 addresses have a nominal charge; Public IPv6 addresses have no charge.  To learn more about IP address pricing in Azure, review the [IP address pricing](https://azure.microsoft.com/pricing/details/ip-addresses) page.
+Public IPv4 addresses have a nominal charge; Public IPv6 addresses have no charge.
+
+To learn more about IP address pricing in Azure, review the [IP address pricing](https://azure.microsoft.com/pricing/details/ip-addresses) page.
 
 ## Limitations for IPv6
 
-* VPN gateways cannot be used in a virtual network with IPv6 enabled, either directly or peered with "UseRemoteGateway".
+* VPN gateways can't be used in a virtual network with IPv6 enabled, either directly or peered with "UseRemoteGateway".
+
 * Public IPv6 addresses are locked at an idle timeout of 4 minutes.
+
 * Azure doesn't support IPv6 communication for containers.
+
 * Use of IPv6-only virtual machines or virtual machines scale sets aren't supported. Each NIC must include at least one IPv4 IP configuration (dual-stack).
-* When adding IPv6 to existing IPv4 deployments, IPv6 ranges can't be added to a virtual network with existing resource navigation links.
+
+* IPv6 ranges can't be added to a virtual network with existing resource navigation links when adding IPv6 to existing IPv4 deployments.
+
 * Forward DNS for IPv6 is supported for Azure public DNS. Reverse DNS isn't supported.
-* Routing Preference and cross-region load-balancing isn't supported.
+
+* Routing Preference and cross-region load balancer aren't supported.
 
 For more information on IPv6 in Azure, see [here](ipv6-overview.md).
 
 ## Next steps
+
 * Learn about [Private IP Addresses in Azure](private-ip-addresses.md)
+
 * [Deploy a VM with a static public IP using the Azure portal](./virtual-network-deploy-static-pip-arm-portal.md)