{"id":"sigv4a-ecdsa-multi-region-signing","text":"SigV4a uses ECDSA (asymmetric cryptography) to derive a public-private keypair, enabling a single signature to be valid across multiple regions — required for multi-region API requests like S3 Multi-Region Access Points.","truth_value":"IN","source":"entries/2026/03/11/IAM-latest-UserGuide-reference_aws-signinghtml.md","source_url":"","source_hash":"389d739937adcf5d","justifications":[],"dependents":[],"metadata":{},"explanation":{"steps":[{"node":"sigv4a-ecdsa-multi-region-signing","truth_value":"IN","reason":"premise"}]}}