Ingress

• mTLS transport plus request signing with HMAC or HTTP signature

• Idempotency key timestamp and nonce with allowed clock skew

Consistency and batching

• Deduplicate using event hash and idempotency to ensure single effect handling

• m of n quorum then batch Merkle root commits to the chain

Operations

• SLA monitors for p95 latency drop rate and signature errors

• Failover retries and dead letter queues

Keys and audit

• Keys stored in HSM or KMS with role based access

• Full audit to a central SIEM and OpenTelemetry pipeline