Update ip-services-custom-ip-global-regional-unified-model.md

note about parent - child ranges

Author: brianlehr

includes/ip-services-custom-ip-global-regional-unified-model.md

@@ -11,7 +11,7 @@ ms.date: 06/04/2024
 
 Before onboarding your range to Azure, you need to decide on the model that would work best for your architecture. For BYOIPv4, Azure offers two deployment models: "global/regional" and "unified".
 
-* The Global/Regional model uses a *parent*/*child* paradigm. In this paradigm, the Microsoft Wide Area Network (WAN) advertises the global (parent) range, and the respective Azure regions advertise the regional (child) ranges. By default, global ranges can be anywhere from /21 to /24 in size, and regional ranges can be from /22 to /26 in size. Regional ranges are dependent on the size of their respective parent range, and they must be at least one level smaller. For example, a global range using /23 would allow a regional range of /24 to /26. Only the global range needs to be validated as part of the provisioning. The regional ranges are derived from the global range in a similar manner to the way public IP prefixes are derived from custom IP prefixes.
+* The Global/Regional model uses a *parent*/*child* paradigm. In this paradigm, the Microsoft Wide Area Network (WAN) advertises the global (parent) range, and the respective Azure regions advertise the regional (child) ranges. By default, global ranges can be anywhere from /21 to /24 in size, and regional ranges can be from /22 to /26 in size. Regional ranges are dependent on the size of their respective parent range, and they must be at least one level smaller. For example, a global range using /23 would allow a regional range of /24 to /26. Only the global range needs to be validated as part of the provisioning. The regional ranges are derived from the global range in a similar manner to the way public IP prefixes are derived from custom IP prefixes.  Regional ranges can be in different subscriptions from the global range, but must be in the same tenant.
 
 * The Unified model is a simplified system where both the Microsoft Wide Area Network (WAN) and the Azure region advertises the same range. By default, a unified range can be anywhere from /21 to /24 in size.