AWS Cloud WAN Routing Policy Guide Adds Global Network Scenarios for Part 2

AWS has published the second installment of its Cloud WAN routing policy guide, providing detailed walkthroughs of how to apply fine-grained routing controls across global networks. The post, released on the AWS Networking and Content Delivery blog, builds on Part 1 with concrete deployment patterns.

Each routing policy in AWS Cloud WAN consists of three core components: match conditions that evaluate route prefixes or BGP attributes, actions that determine how matching routes are handled, and path selection logic that influences the final route choice. Part 2 applies these components to real-world topologies such as hub-and-spoke and transit VPC architectures.

Scenario-based guidance for route propagation and path selection

The guide demonstrates how to prevent routes from certain segments from propagating into other segments using match conditions on AS_PATH or community tags, and how to set preferred paths for traffic between specific regions. AWS recommends these policies for organizations that operate across multiple regions and need to isolate development, production, or partner environments while maintaining connectivity.

• Match conditions can filter based on IP prefix length, BGP extended communities, or AS_PATH contents.
• Actions include permitting or denying route propagation, preferring a particular attachment, or modifying AS_PATH attributes.
• Path selection can be overridden using segment-level preferences to direct traffic through specific intermediate regions.

Implications for multi-region network operators

The addition of detailed scenario documentation helps network architects move from theory to production without relying solely on trial and error. AWS Cloud WAN, introduced in 2021, already supported centralized network policies, but the granularity shown in Part 2 addresses a common customer request: controlling inter-region traffic flows at scale without complex on-premise SD-WAN overlays.

AWS did not announce any new pricing or feature releases alongside the blog post. The scenarios are available immediately through the AWS Cloud WAN console and API, with no additional charges beyond standard Cloud WAN usage fees. Network teams using Cloud WAN can implement the examples as a starting point and then customize match conditions to fit their own route tables and security requirements.