Merge pull request #279641 from aimee-littleton/patch-208

Update integrate-with-nat-gateway.md

Author: prmerger-automator[bot]

articles/firewall/integrate-with-nat-gateway.md

@@ -14,7 +14,7 @@ ms.custom: devx-track-azurepowershell, devx-track-azurecli
 
 Azure Firewall provides 2,496 SNAT ports per public IP address configured per backend virtual machine scale set instance (Minimum of two instances), and you can associate up to [250 public IP addresses](./deploy-multi-public-ip-powershell.md). Depending on your architecture and traffic patterns, you might need more than the 1,248,000 available SNAT ports with this configuration. For example, when you use it to protect large [Azure Virtual Desktop deployments](./protect-azure-virtual-desktop.md) that integrate with Microsoft 365 Apps.
 
-One of the challenges with using a large number of public IP addresses is when there are downstream IP address filtering requirements. Azure Firewall randomly selects the source public IP address to use for a connection, so you need to allow all public IP addresses associated with it. Even if you use [Public IP address prefixes](../virtual-network/ip-services/public-ip-address-prefix.md) and you need to associate 250 public IP addresses to meet your outbound SNAT port requirements, you still need to create and allow 16 public IP address prefixes.
+One of the challenges with using a large number of public IP addresses is when there are downstream IP address filtering requirements. When Azure Firewall is associated with multiple public IP addresses, you need to apply the filtering requirements across all public IP addresses associated with it. Even if you use [Public IP address prefixes](../virtual-network/ip-services/public-ip-address-prefix.md) and you need to associate 250 public IP addresses to meet your outbound SNAT port requirements, you still need to create and allow 16 public IP address prefixes.
 
 A better option to scale and dynamically allocate outbound SNAT ports is to use an [Azure NAT Gateway](../virtual-network/nat-gateway/nat-overview.md). It provides 64,512 SNAT ports per public IP address and supports up to 16 public IP addresses. This effectively provides up to 1,032,192 outbound SNAT ports. Azure NAT Gateway also [dynamically allocates SNAT ports](/azure/nat-gateway/nat-gateway-resource#nat-gateway-dynamically-allocates-snat-ports) on a subnet level, so all the SNAT ports provided by its associated IP addresses is available on demand to provide outbound connectivity.