Security groups filter both traffic directions, and overly broad outbound permissions can undermine restrictive inbound application topology; that addresses bidirectional ENI-level traffic-policy assessment, rather than explicit subnet-level denial of hostile CIDR traffic.

DNS Firewall evaluates resolver queries against domain rule groups and can block specified malicious names before resolution; this belongs to domain-based protection of VPC DNS resolution, while the problem is explicit subnet-level denial of hostile CIDR traffic.

WAF inspects inferred geographic source attributes on HTTP requests and can block requests that match the location policy; this changes geography-based web request enforcement, not the necessary explicit subnet-level denial of hostile CIDR traffic.

Stateful security groups can match source security-group identity rather than broadly allowing an entire VPC or unpredictable load-balancer addresses; that addresses stateful source-restricted access from load balancer to target, rather than stateful firewall flow symmetry across AZs.

Centralized egress controls outbound paths at routing and firewall layers while workload subnets remain unexposed to an Internet gateway; this belongs to inspected outbound connectivity from private workloads, while the problem is stateful firewall flow symmetry across AZs.

Stateful inspection depends on flow context; indiscriminate mid-session target changes can reset sessions even when the replacement is healthy; this changes session-state integrity under security appliance scaling, not the necessary stateful firewall flow symmetry across AZs.

This produces managed stateful deep inspection of VPC flows: Network Firewall inspects flows with stateful rule evaluation and can apply supported Suricata or domain-oriented rules at routed inspection endpoints; the stem instead tests stateful firewall flow symmetry across AZs.

Firewall Manager centrally applies and audits supported protections across eligible accounts rather than relying on each workload team; that addresses organization-wide application firewall policy enforcement, rather than domain-based protection of VPC DNS resolution.

The ordered NACL rule set evaluates every matching packet direction and can block identified sources without instance-by-instance rule changes; this belongs to explicit subnet-level denial of hostile CIDR traffic, while the problem is domain-based protection of VPC DNS resolution.

Network Firewall inspects flows with stateful rule evaluation and can apply supported Suricata or domain-oriented rules at routed inspection endpoints; this changes managed stateful deep inspection of VPC flows, not the necessary domain-based protection of VPC DNS resolution.

CloudFront WAF integration evaluates viewer HTTP requests at the edge, before they reach the distribution's origin; that addresses edge-level web filtering for a CDN, rather than geography-based web request enforcement.

WAF rate-based rules count recent matching web requests and can block or challenge clients that exceed configured thresholds; this belongs to per-source HTTP request-rate enforcement, while the problem is geography-based web request enforcement.

In the application-layer web request filtering workflow, WAF evaluates application-layer request properties and managed or custom rules to block malicious HTTP patterns before forwarding; the current case needs geography-based web request enforcement.

An application-aware proxy can evaluate HTTP host or URL context beyond simple IP and port access controls; that addresses higher-layer outbound web destination governance, rather than bidirectional ENI-level traffic-policy assessment.

Interface endpoints use ENIs and security groups; traffic needs network admission at those endpoint interfaces; this belongs to private endpoint interface security-group authorization, while the problem is bidirectional ENI-level traffic-policy assessment.

The ordered NACL rule set evaluates every matching packet direction and can block identified sources without instance-by-instance rule changes; this changes explicit subnet-level denial of hostile CIDR traffic, not the necessary bidirectional ENI-level traffic-policy assessment.

Appliance mode preserves flow symmetry through a stateful inspection VPC attachment so connection tracking can evaluate both directions; this belongs to stateful firewall flow symmetry across AZs, while the problem is demonstrated fail-closed forwarding behavior.

Routing must make the inspection hop the viable path; merely deploying firewalls does not ensure packets traverse them; this changes mandatory central inspection via transit routing, not the necessary demonstrated fail-closed forwarding behavior.

In the session-state integrity under security appliance scaling workflow, stateful inspection depends on flow context; indiscriminate mid-session target changes can reset sessions even when the replacement is healthy; the current case needs demonstrated fail-closed forwarding behavior.

An egress-only internet gateway forwards IPv6 Internet traffic but does not perform IPv6-to-IPv4 protocol translation.

A DNS response alone cannot make a service with only an IPv4 listener accept native IPv6 packets. A dual-stack ALB or native IPv6-serving endpoint is still required for IPv6 client connectivity.

IPv6-only clients cannot originate IPv4 connections directly. DNS64 and a NAT64 route supply the IPv6-to-IPv4 bridge.

An IPv4 CIDR authorizes IPv4 packets only. Expanding it cannot permit IPv6 clients and would expose more IPv4 sources.

Routing reachability cannot override a security group that has no matching IPv6 HTTPS allow rule. The instance or load-balancer security group must explicitly permit the IPv6 source range and destination port.

Stateful return traffic is automatically allowed for admitted connections, but an inbound connection still requires an ingress rule.

A NAT gateway is not a public IPv6 inbound authorization mechanism for a dualstack application. IPv6 inbound requires supported IPv6 addressing, routes and security controls rather than IPv4 NAT translation.

Firewall Manager coordinates supported WAF, Shield, network firewall, and security-group policies organization-wide; that addresses centralized multi-account network security policy rollout, rather than highly available virtual firewall insertion.

Stateful inspection depends on flow context; indiscriminate mid-session target changes can reset sessions even when the replacement is healthy; this belongs to session-state integrity under security appliance scaling, while the problem is highly available virtual firewall insertion.

In the scalable inline third-party firewall appliances workflow, gateway Load Balancer transparently distributes encapsulated flows to virtual appliances, while endpoints provide route-table insertion points; the current case needs highly available virtual firewall insertion.

WAF evaluates application-layer request properties and managed or custom rules to block malicious HTTP patterns before forwarding; that addresses application-layer web request filtering, rather than higher-layer outbound web destination governance.

Egress-only internet gateways allow IPv6 outbound connections and their replies without offering public initiation into the VPC; this belongs to stateful-looking outbound-only IPv6 gateway control, while the problem is higher-layer outbound web destination governance.

In the geography-based web request enforcement workflow, WAF inspects inferred geographic source attributes on HTTP requests and can block requests that match the location policy; the current case needs higher-layer outbound web destination governance.

Firewall rules protect only traffic traversing their enforcement points; route bypass makes those policies ineffective; that addresses enforced packet path through inspection resources, rather than mandatory central inspection via transit routing.

Whether traffic bypasses, drops, or reroutes on failure depends on the chosen firewall and routing architecture, not simply on a healthy policy configuration; this belongs to demonstrated fail-closed forwarding behavior, while the problem is mandatory central inspection via transit routing.

In the inspected outbound connectivity from private workloads workflow, centralized egress controls outbound paths at routing and firewall layers while workload subnets remain unexposed to an Internet gateway; the current case needs mandatory central inspection via transit routing.