Networkmanager Core Network Policy: A Deep Dive in AWS Resources & Best Practices to Adopt

Modern enterprise networking demands sophisticated orchestration across diverse environments, cloud regions, and hybrid architectures. Recent research by Gartner indicates that 75% of organizations will have deployed multiple cloud networking technologies by 2025, creating complex interdependencies that require centralized policy management. AWS Cloud WAN, serving over 10,000 active customers globally, represents a significant shift toward software-defined networking at scale. The Networkmanager Core Network Policy sits at the heart of this transformation, acting as the central nervous system that governs how network traffic flows across your entire AWS infrastructure.

Organizations migrating from traditional hub-and-spoke architectures to cloud-native mesh networks often struggle with maintaining consistent security postures and routing policies across distributed environments. The Core Network Policy addresses these challenges by providing a single source of truth for network behavior, enabling teams to define once and deploy everywhere. This centralized approach has proven to reduce network configuration errors by up to 60% while improving deployment velocity for infrastructure changes. For comprehensive dependency mapping and risk analysis of your Core Network Policy changes, explore how Overmind maps networkmanager-core-network relationships.

In this blog post we will learn about what Networkmanager Core Network Policy is, how you can configure and work with it using Terraform, and learn about the best practices for this service.

What is Networkmanager Core Network Policy?

Networkmanager Core Network Policy is a comprehensive JSON-based configuration document that defines the routing, security, and operational behavior of AWS Cloud WAN core networks. It serves as the authoritative specification for how network traffic should flow between different segments, regions, and edge locations within your global network architecture.

The Core Network Policy operates on a declarative model where network administrators define desired network states and behaviors rather than individual configuration commands. This approach enables consistent policy enforcement across all network endpoints, regardless of their geographic location or underlying infrastructure. The policy engine automatically translates high-level intent into specific routing rules, security group configurations, and network access control lists. By maintaining this abstraction layer, organizations can implement complex network topologies while reducing operational complexity and potential configuration drift. Understanding these relationships becomes crucial when planning changes, as modifications to core network policies can impact numerous downstream resources. Overmind's networkmanager-core-network analysis provides visibility into these interdependencies, helping teams assess the full scope of policy modifications before implementation.

Policy-Driven Network Architecture

The Core Network Policy embraces a policy-driven approach to network management, where business requirements and security constraints are translated into machine-readable configurations. This methodology represents a fundamental shift from traditional network management practices that rely heavily on manual configuration and tribal knowledge. Within the policy framework, network administrators can define segments that logically group related resources, establish routing relationships between these segments, and implement security boundaries that align with organizational requirements.

Each policy contains multiple sections that work together to create a comprehensive network blueprint. The core network edges define connection points where traffic enters and exits the network, while network segments provide logical isolation and traffic routing rules. Attachment policies determine how VPCs, Direct Connect gateways, and other AWS resources can connect to the core network, creating a flexible yet controlled networking environment. This architectural approach enables organizations to implement zero-trust networking principles while maintaining the performance and reliability requirements of modern applications.

Dynamic Policy Evaluation and Enforcement

The Core Network Policy engine continuously evaluates network configurations against defined policies, automatically adjusting routing tables and security rules as network conditions change. This dynamic evaluation ensures that network behavior remains consistent with organizational intent, even as infrastructure scales or evolves. The policy engine maintains real-time awareness of network topology changes, automatically updating routing decisions when new attachments are created or existing connections are modified.

Policy evaluation occurs at multiple levels within the network stack, from initial connection establishment through ongoing traffic flow management. The system validates that proposed network changes comply with security policies before implementing routing updates, preventing misconfigurations that could compromise network security or performance. This multi-layered evaluation process provides organizations with confidence that their network infrastructure operates according to defined standards, regardless of the complexity of the underlying topology. When planning policy modifications, teams need comprehensive visibility into current network relationships to avoid unintended consequences. Overmind's Core Network Policy mapping reveals these complex interdependencies, enabling safer policy updates through better understanding of potential impacts.

Strategic Network Governance and Compliance

The Networkmanager Core Network Policy serves as a cornerstone for enterprise network governance, providing organizations with the tools necessary to implement consistent security and operational standards across distributed infrastructure. According to recent industry research, organizations using centralized network policy management report 40% fewer security incidents and 25% faster incident response times compared to those relying on distributed configuration management approaches.

Centralized Policy Management at Scale

Organizations operating in multiple AWS regions and accounts benefit significantly from centralized policy management capabilities. The Core Network Policy enables network administrators to define global routing and security policies that automatically propagate across all network endpoints, eliminating the need for manual configuration replication. This centralized approach ensures consistency in network behavior while reducing the administrative burden associated with managing distributed network infrastructure.

The policy framework supports hierarchical policy inheritance, allowing organizations to define baseline security and routing policies at the organizational level while permitting localized customization for specific business units or applications. This flexibility enables enterprise-scale deployments while maintaining the granular control necessary for compliance with industry regulations and organizational security requirements. Teams can implement different security postures for development, staging, and production environments while ensuring all networks adhere to fundamental organizational standards.

Automated Compliance and Audit Capabilities

Core Network Policies provide built-in audit trails and compliance reporting capabilities that simplify regulatory adherence and security assessments. The policy engine automatically logs all configuration changes, routing decisions, and security policy evaluations, creating comprehensive audit records that support compliance requirements across various industries. These audit capabilities extend beyond basic logging to include policy drift detection and automated remediation suggestions.

The system continuously monitors network configurations against defined policies, identifying deviations that could indicate security risks or compliance violations. When policy violations are detected, the system can automatically trigger remediation workflows or alert security teams to investigate potential issues. This proactive approach to compliance management helps organizations maintain security postures while reducing the manual effort required for ongoing compliance monitoring.

Enterprise Integration and Workflow Optimization

Modern enterprises require network policies that integrate seamlessly with existing development and operational workflows. The Core Network Policy framework supports API-driven configuration management, enabling integration with Infrastructure as Code tools, CI/CD pipelines, and automated deployment systems. This integration capability allows organizations to treat network configurations as code, applying the same version control, testing, and deployment practices used for application development.

The policy framework includes support for staging and testing environments, allowing organizations to validate policy changes before deploying them to production networks. This testing capability is particularly valuable for complex network modifications that could impact multiple services or applications. By providing safe testing environments, the Core Network Policy framework enables organizations to maintain high availability while implementing necessary network changes and improvements.

Key Features and Capabilities

Segment-Based Network Isolation

The Core Network Policy implements sophisticated segment-based isolation that enables organizations to create logical network boundaries without requiring complex VLAN configurations or physical network segregation. Network segments can be defined based on business requirements, security classifications, or operational needs, providing flexible isolation mechanisms that adapt to changing organizational requirements. Each segment maintains its own routing table and security policies while enabling controlled communication with other segments through explicit policy definitions.

Segment isolation extends beyond basic traffic separation to include advanced features such as bandwidth allocation, quality of service prioritization, and traffic inspection capabilities. Organizations can implement different security postures for each segment while maintaining the ability to selectively enable cross-segment communication based on business requirements. This granular control enables implementation of zero-trust networking principles while preserving the performance characteristics required for modern applications.

Dynamic Routing and Path Optimization

The policy engine includes advanced routing capabilities that automatically optimize network paths based on performance metrics, cost considerations, and availability requirements. The system continuously monitors network performance across all available paths, automatically adjusting routing decisions to maintain optimal performance while adhering to defined policies. This dynamic routing capability ensures that network traffic follows the most efficient paths while maintaining compliance with security and operational requirements.

Path optimization extends beyond basic routing to include predictive analytics that anticipate network congestion and proactively adjust routing decisions to maintain performance levels. The system can automatically implement load balancing across multiple paths, providing both performance benefits and increased resilience against network failures. These capabilities enable organizations to maintain high-performance network connectivity while reducing operational complexity and manual intervention requirements.

Advanced Security Policy Integration

Core Network Policies integrate seamlessly with AWS security services, enabling automated security policy enforcement across all network endpoints. The policy framework can automatically configure security groups, network ACLs, and AWS WAF rules based on defined security requirements, ensuring consistent security postures across distributed infrastructure. This integration eliminates the need for manual security configuration while providing the flexibility necessary for complex security requirements.

The security integration includes support for dynamic security group management, where security rules are automatically updated based on network topology changes or policy modifications. This capability ensures that security configurations remain aligned with network policies even as infrastructure evolves, reducing the risk of security gaps or misconfigurations that could compromise network security.

Multi-Region and Multi-Account Support

The Core Network Policy framework provides native support for multi-region and multi-account deployments, enabling organizations to implement consistent network policies across their entire AWS infrastructure. The policy engine automatically handles the complexities associated with cross-region networking, including latency optimization, availability zone selection, and regional failover scenarios. This multi-region support enables organizations to implement global network architectures while maintaining local performance characteristics.

Multi-account support extends beyond basic connectivity to include sophisticated access control and billing allocation capabilities. Organizations can implement different security and operational policies for each account while maintaining the ability to implement organization-wide standards and security requirements. This flexibility enables enterprise-scale deployments while preserving the isolation and security benefits of multi-account architectures.

Integration Ecosystem

The Networkmanager Core Network Policy integrates with a comprehensive ecosystem of AWS networking and security services, creating a unified platform for enterprise network management. This integration approach ensures that network policies work seamlessly with existing AWS infrastructure while providing the flexibility necessary for complex enterprise deployments. The policy framework serves as the central coordination point for network configuration across multiple AWS services, eliminating the need for manual configuration synchronization and reducing the risk of configuration drift.

At the time of writing there are 25+ AWS services that integrate with Networkmanager Core Network Policy in some capacity. These integrations span across networking, security, monitoring, and management services, creating a comprehensive platform for enterprise network operations. Key integrations include VPC attachments, Direct Connect gateway connections, VPN gateway integrations, and Transit Gateway interconnections that enable seamless connectivity across hybrid and multi-cloud environments.

The integration ecosystem extends beyond basic connectivity to include advanced services such as AWS CloudWatch for monitoring and alerting, AWS Config for configuration management and compliance tracking, and AWS CloudTrail for audit logging and security analysis. Overmind's VPC mapping capabilities provide crucial visibility into these VPC attachment relationships, helping teams understand how policy changes might impact connected resources across their network infrastructure.

Network monitoring and observability integrations enable real-time visibility into network performance, security events, and policy compliance status. The policy framework automatically configures monitoring systems to track network behavior against defined policies, providing organizations with comprehensive visibility into network operations and security postures. These monitoring capabilities include automated alerting for policy violations, performance degradation, and security incidents that require immediate attention.

The management and automation integrations enable seamless incorporation of Core Network Policies into existing DevOps and Infrastructure as Code workflows. Organizations can manage network policies using the same tools and processes used for application deployment, ensuring consistency in operational practices while reducing the learning curve for development and operations teams. This integration capability is particularly valuable for organizations implementing continuous integration and deployment practices for infrastructure management.

Pricing and Scale Considerations

The Networkmanager Core Network Policy operates within the AWS Cloud WAN pricing model, which follows a consumption-based approach with no upfront costs or long-term commitments. Organizations pay for the core network hours, data processing, and data transfer associated with their network usage, providing cost transparency and flexibility for varying usage patterns. The pricing structure includes a free tier that provides 5 GB of data processing per month, enabling organizations to evaluate the service before committing to production deployments.

Core network hourly charges apply to each core network in your account, regardless of the number of policies or segments configured within that network. This pricing model encourages consolidation of network resources while providing the flexibility to implement complex network topologies without additional policy-related charges. Data processing charges apply to traffic that flows through the core network, with different rates for different types of data processing operations such as routing, security policy evaluation, and cross-region traffic forwarding.

Scale Characteristics

The Core Network Policy framework is designed to support enterprise-scale deployments with virtually unlimited scalability in terms of network segments, routing rules, and policy complexity. Individual core networks can support hundreds of VPC attachments, thousands of routing rules, and complex multi-region topologies without performance degradation. The policy evaluation engine uses distributed processing to ensure that policy enforcement remains responsive even as network complexity increases.

Performance characteristics include sub-second policy evaluation for most routing decisions and automatic scaling of policy enforcement resources based on network traffic patterns. The system maintains consistent performance across varying loads while providing the reliability and availability characteristics required for mission-critical network infrastructure. Regional deployment capabilities ensure that policy evaluation and enforcement occur close to network endpoints, minimizing latency and maximizing performance for end users.

Enterprise Considerations

Enterprise deployments benefit from advanced features such as dedicated policy evaluation resources, priority support, and advanced monitoring capabilities that provide enhanced visibility into network operations and policy compliance. These enterprise features include dedicated technical account management, architecture reviews, and custom integration support that helps organizations optimize their network deployments for specific business requirements.

The service integrates with AWS Organizations for centralized billing and management, enabling enterprise-scale deployments with consistent governance and cost allocation across multiple accounts and business units. Advanced audit and compliance features provide the documentation and reporting capabilities required for regulatory compliance and security certifications. For organizations requiring additional network control, AWS also offers alternatives such as Transit Gateway and VPC peering connections. However, for infrastructure running on AWS this is the most comprehensive solution for implementing policy-driven network management at scale.

Cost optimization strategies include right-sizing core network deployments, implementing efficient routing policies that minimize data processing charges, and utilizing regional deployment strategies that reduce cross-region data transfer costs. Organizations can implement cost monitoring and alerting to track network usage patterns and identify opportunities for optimization while maintaining the performance and security characteristics required for their applications.

Managing Networkmanager Core Network Policy using Terraform

Managing Networkmanager Core Network Policy through Terraform requires careful consideration of the policy's JSON structure and its dependencies on other network resources. The policy configuration can be complex, involving multiple segments, routing rules, and attachment policies that must be coordinated to create a functional network architecture.

Enterprise Multi-Region Core Network Policy

This configuration demonstrates how to implement a comprehensive enterprise network policy that supports multiple regions, business units, and security requirements. The policy includes development, staging, and production segments with appropriate isolation and routing rules.

This configuration establishes a core network policy with production and development segments, each with specific characteristics and routing rules. The policy ensures proper network segmentation while allowing controlled connectivity between different environments.

Advanced Policy Configuration with Complex Routing

For enterprises requiring sophisticated network topologies, you can create more complex policies that handle advanced routing scenarios and conditional logic.

This advanced configuration demonstrates enterprise-grade network segmentation with multiple segments, conditional routing, and attachment policies that automatically assign resources to appropriate network segments based on tags.

Parameter Explanations

The core_network_id parameter specifies which core network this policy applies to, creating a direct relationship between the policy and the underlying network infrastructure. The policy_document contains the JSON-encoded policy definition that governs network behavior.

Within the policy document, the core_network_configuration section defines global network settings including ASN ranges, edge locations, and ECMP support. The segments array creates isolated network segments with specific characteristics and access controls.

The segment_actions array defines routing rules and connectivity between segments, while attachment_policies provide conditional logic for automatically assigning resources to appropriate segments based on tags or other criteria.

Dependencies and Integration

Core network policies have several important dependencies that must be considered when designing your Terraform configuration. The policy depends on the existence of a core network, which in turn depends on a global network resource.

The policy also integrates with VPC attachments, VPN connections, and other network resources that connect to the core network. These dependencies should be properly managed through Terraform's resource dependency system to ensure correct deployment order.

Best practices for Networkmanager Core Network Policy

The Networkmanager Core Network Policy is a foundational element that determines how your AWS network infrastructure operates. Following proven practices when designing and implementing these policies can mean the difference between a robust, scalable network and one that becomes a bottleneck or security risk.

Policy Design and Structure

Why it matters: A well-structured core network policy provides clear governance for network behavior while maintaining flexibility for future changes. Poor policy design can lead to network segmentation issues, routing conflicts, and operational complexity.

Implementation: Design your core network policy with a hierarchical structure that reflects your organizational needs. Start with broad network segments and progressively define more specific rules. Use descriptive naming conventions that clearly indicate the purpose of each policy rule.

Create policies that are modular and reusable across different network segments. This approach reduces configuration drift and makes it easier to maintain consistency across your network infrastructure.

Security-First Policy Configuration

Why it matters: Core network policies control traffic flow and access patterns across your entire network infrastructure. Inadequate security controls in these policies can expose your organization to lateral movement attacks and data exfiltration risks.

Implementation: Implement a default-deny approach where traffic is explicitly allowed rather than implicitly permitted. Define clear boundaries between different network zones and ensure that inter-zone communication follows the principle of least privilege.

Regularly audit your policy configurations to ensure they align with your security posture and haven't developed configuration drift over time.

Scalability and Performance Optimization

Why it matters: Network policies directly impact performance and scalability. Overly complex policies can introduce latency, while insufficient planning can create bottlenecks as your network grows.

Implementation: Design policies with growth in mind. Plan for future expansion by reserving IP address ranges and considering how new regions or availability zones will integrate into your existing policy structure.

Configure appropriate ASN ranges that provide room for expansion while avoiding conflicts with existing network infrastructure. Consider using private ASN ranges (64512-65534) for internal network segments.

Version Control and Change Management

Why it matters: Core network policies are critical infrastructure components that affect connectivity across your entire environment. Uncontrolled changes can lead to widespread outages and security vulnerabilities.

Implementation: Implement a robust change management process that includes version control, testing, and rollback procedures. Always maintain previous policy versions to enable quick recovery if issues arise.

Use descriptive commit messages and documentation to track why specific policy changes were made. This historical context becomes invaluable when troubleshooting issues or planning future modifications.

Monitoring and Alerting

Why it matters: Without proper monitoring, network policy issues can go undetected until they cause significant business impact. Proactive monitoring enables quick identification and resolution of policy-related problems.

Implementation: Set up comprehensive monitoring for policy changes, attachment status, and network performance metrics. Create alerts for policy deployment failures, attachment timeouts, and unusual traffic patterns.

Monitor policy execution times and success rates to identify potential performance issues before they impact users.

Documentation and Knowledge Management

Why it matters: Core network policies are complex configurations that require deep understanding to maintain effectively. Poor documentation leads to operational risk and increases the likelihood of configuration errors.

Implementation: Maintain comprehensive documentation that explains not just what each policy does, but why it was configured that way. Include network diagrams, IP address allocations, and dependencies between different policy components.

Document standard operating procedures for common policy changes, including testing procedures and rollback steps. This documentation becomes critical during incident response and when onboarding new team members.

Testing and Validation

Why it matters: Network policy changes can have far-reaching consequences that aren't immediately apparent. Thorough testing helps identify potential issues before they affect production traffic.

Implementation: Establish a testing framework that validates policy changes in a controlled environment before deployment. Use network simulation tools to model traffic patterns and identify potential bottlenecks or security gaps.

Implement automated testing where possible to catch common configuration errors and ensure consistency across deployments.

Disaster Recovery Planning

Why it matters: Core network policies are single points of failure that can impact your entire network infrastructure. Having a solid disaster recovery plan ensures business continuity during policy-related outages.

Implementation: Develop and regularly test procedures for quickly reverting policy changes, restoring from backups, and maintaining network connectivity during policy failures. Keep multiple versions of working policies readily available for emergency use.

Document emergency contact procedures and escalation paths for policy-related incidents. Ensure that disaster recovery procedures are accessible and understandable to all team members who might need to execute them.

Following these best practices creates a foundation for reliable, secure, and scalable network infrastructure that can adapt to changing business needs while maintaining operational excellence.

Product Integration

The Networkmanager Core Network Policy integrates with a comprehensive ecosystem of AWS networking and management services to provide robust network governance capabilities. This integration ensures that your core network policies work seamlessly with existing infrastructure while maintaining security and performance standards.

At the time of writing, there are over 30 AWS services that integrate with Networkmanager Core Network Policy in some capacity. This extensive integration capability makes it a cornerstone service for enterprise network management, particularly for organizations running complex, multi-region deployments.

The policy service works closely with AWS Cloud WAN, enabling centralized management of wide area networks across multiple AWS accounts and regions. This integration allows you to define consistent network policies that apply across your entire global network infrastructure, ensuring uniform security and routing behaviors regardless of geographic location.

Integration with AWS Transit Gateway provides advanced routing capabilities, allowing core network policies to control traffic flow between different network segments. This relationship enables sophisticated network segmentation strategies while maintaining the flexibility to adapt to changing business requirements.

The service also integrates with AWS Direct Connect, allowing core network policies to govern hybrid cloud connectivity. This integration is particularly valuable for organizations that need to maintain consistent network policies across on-premises and cloud environments, ensuring seamless connectivity while enforcing security boundaries.

Through its integration with AWS Route 53, the Networkmanager Core Network Policy can influence DNS resolution behaviors, enabling advanced traffic routing strategies based on network policies. This integration supports sophisticated load balancing and failover scenarios that align with your overall network architecture.

Use Cases

Global Network Standardization

Organizations with multi-region deployments often struggle with maintaining consistent network policies across different geographic locations. The Networkmanager Core Network Policy addresses this challenge by providing a centralized framework for defining and enforcing network behaviors globally. For example, a multinational corporation can use core network policies to ensure that all regional offices follow the same security protocols and routing rules, regardless of their local infrastructure variations. This standardization reduces complexity while improving security posture across the entire organization.

Hybrid Cloud Network Management

Many enterprises operate hybrid cloud environments where on-premises resources need to integrate seamlessly with AWS services. Core network policies provide the governance framework necessary to manage these complex hybrid deployments effectively. By defining policies that span both cloud and on-premises resources, organizations can maintain consistent security policies, optimize traffic routing, and ensure compliance requirements are met across all network segments. This approach simplifies network management while providing the flexibility needed for modern hybrid architectures.

Multi-Account Network Governance

Large organizations typically operate multiple AWS accounts for different business units or environments. The Networkmanager Core Network Policy enables centralized governance of network behaviors across these accounts while maintaining appropriate isolation and security boundaries. This capability is particularly valuable for organizations that need to enforce consistent network policies across development, staging, and production environments, ensuring that security standards are maintained throughout the entire software development lifecycle.

Limitations

Policy Complexity Management

While the Networkmanager Core Network Policy provides powerful capabilities, managing complex policy configurations can become challenging as network requirements evolve. Organizations may find themselves dealing with intricate policy rules that become difficult to maintain and troubleshoot over time. This complexity can lead to configuration errors or unintended network behaviors that impact application performance or security.

Regional Availability Constraints

The Networkmanager Core Network Policy is not available in all AWS regions, which can limit its applicability for organizations with global footprints. Organizations operating in regions where the service is not available may need to implement alternative network governance strategies, leading to inconsistent policy enforcement across their global infrastructure.

Performance Impact Considerations

Implementing comprehensive core network policies can introduce additional latency in network operations, particularly for complex routing decisions or extensive policy evaluations. Organizations need to carefully balance policy comprehensiveness with performance requirements, especially for latency-sensitive applications or high-throughput network scenarios.

Integration Learning Curve

The extensive integration capabilities of the Networkmanager Core Network Policy require significant expertise to implement effectively. Organizations may need to invest in training or specialized personnel to fully leverage the service's capabilities, which can impact project timelines and resource allocation.

Conclusions

The Networkmanager Core Network Policy service is a sophisticated foundation for enterprise network governance that enables organizations to maintain consistent, secure, and efficient network operations across complex AWS environments. It supports comprehensive network management strategies while providing the flexibility needed for modern cloud architectures.

The service's extensive integration ecosystem makes it particularly valuable for organizations operating multi-region or hybrid cloud deployments. However, you will most likely integrate your own custom network management applications with the Networkmanager Core Network Policy as well. Managing complex policy configurations and their interactions with other network services requires careful planning and ongoing maintenance to avoid unintended consequences.

With Overmind's risk assessment capabilities, you can better understand the potential impact of core network policy changes before implementation. Our platform helps identify dependencies and potential risks associated with policy modifications, enabling you to make informed decisions about network changes while minimizing the risk of service disruptions.