Security Model

How Restate Cloud BYOC secures the control channel, infrastructure, and customer data.

Restate Cloud BYOC is designed around three principles: least privilege, egress-only connectivity, and customer ownership of infrastructure. Restate never holds credentials to your cloud account.

Control channel

The BYOC deployment has three network connections, all initiated from within your account:

Connection	Direction	Protocol	Purpose
Deployment agent → Restate control plane	Egress from your account	HTTPS (long-polling)	Pulls provisioning and management jobs
Restate control plane → Kubernetes API	Inbound to cluster API endpoint	HTTPS with bearer token	Manages Restate environments (CRDs, namespaces)
Metrics collector → Restate metrics store	Egress from your account	HTTPS	Ships operational metrics for monitoring and alerting

The deployment agent uses an egress-only polling model — it reaches out to Restate’s control plane to check for work. Restate’s control plane never initiates connections into your account for provisioning or management operations.

Restate’s control plane connects to your Kubernetes API to manage Restate environments. This connection uses a bearer token scoped to a limited Kubernetes RBAC role. You can restrict access to the Kubernetes API endpoint by IP allowlisting.

What crosses the control channel

Sent to your cluster:

Category	Examples
Environment manifests	RestateCluster CRDs specifying resource limits, replicas, configuration
Container image references	Image tags (pulled from registry by cluster, not transferred over control channel)
Configuration	Restate server configuration (non-sensitive)
Signing keys	Public keys for request authentication (stored as Kubernetes Secrets in-cluster)

Received from your cluster:

Category	Examples
Health status	Pod readiness, cluster status
Resource metrics	CPU/memory usage, storage utilization
Environment metadata	Version info, replica count

What does NOT cross the control channel:

• Customer application data or invocation payloads
• State stored in Restate
• Customer secrets or credentials
• Application logs (retained in your account)

Bootstrap security

The foundation template is a standard CloudFormation stack (AWS) or ARM template (Azure) that you deploy yourself. It creates scoped roles for the deployment agent.

AWS

The CloudFormation template creates an IAM role for the deployment agent with the following permissions, scoped to the install’s resources:

Permission	Scope	Purpose
Resource management	Install resources	Create and manage EKS, VPC, S3, and supporting resources
EKS cluster admin	Install’s EKS cluster	Deploy Helm charts and Kubernetes manifests via the Kubernetes API
Resource provider registration	Subscription (AWS account)	Register required AWS service providers

All IAM roles follow least-privilege principles and are scoped to the resources created by the stack.

Azure

The ARM template creates a managed identity for the deployment agent (a Virtual Machine Scale Set) with the following role assignments:

Role	Scope	Purpose
Contributor	Resource group	Create and manage AKS, VNet, storage, and supporting resources
Role Based Access Control Administrator	Resource group	Create downstream role assignments (Key Vault access, network, DNS)
Azure Kubernetes Service RBAC Cluster Admin	Resource group	Deploy Helm charts and Kubernetes manifests via Azure RBAC
Custom: resource provider registration	Subscription	Register required Azure resource providers (*/register/action only)

The “Role Based Access Control Administrator” role is required because the deployment agent creates these downstream role assignments during infrastructure provisioning:

Downstream role	Assigned to	Purpose
Key Vault Secrets User	AKS Secrets Store CSI driver	Mount the Restate region secret key from Key Vault into pods
Network Contributor	AKS cluster identity	Manage load balancers and network resources
DNS Zone Contributor	cert-manager identity	Create DNS records for TLS certificate validation

All roles are scoped to the install’s resource group, except the resource provider registration role which is subscription-scoped but limited to */register/action.

“Role Based Access Control Administrator” is narrower than “Owner” — it can only manage role assignments, not create or delete resources. It is the minimum privilege required to create the downstream assignments listed above.

Infrastructure security

Compute

Kubernetes clusters run on dedicated cloud-managed virtual machines:

Layer	AWS	Azure
Compute	EC2 instances (Nitro hypervisor)	Azure VMs (Hyper-V isolated)
Container runtime	containerd	containerd
Kubernetes	Amazon EKS (managed control plane)	Azure AKS (managed control plane)
Architecture	ARM64 (Graviton / Ampere)	ARM64 (Ampere)

Instance security features include IMDSv2 enforcement (AWS), encrypted storage at rest (AES-256), and no local ephemeral storage (all data on network-attached volumes).

Patching

Component	Method	Frequency
Node OS	Automated drift detection	Within 24-48 hours of new AMI/image release
Kubernetes	Managed cloud provider upgrades	Per provider schedule, coordinated with customer
Restate components	Rolling deployment	As releases are published
Container images	Image updates	As vulnerabilities are patched

Vulnerability response targets:

Severity	Response time	Resolution target
Critical (CVSS 9.0+)	8 hours	24 hours
High (CVSS 7.0-8.9)	24 hours	7 days
Medium (CVSS 4.0-6.9)	72 hours	14 days
Low (CVSS < 4.0)	Best effort	Next maintenance window

Network isolation

Each BYOC deployment runs in its own VPC with private subnets across multiple availability zones. Restate environments are isolated via Kubernetes NetworkPolicies:

• Ingress: only the ingress proxy and metrics collector can reach environment pods
• Egress: DNS, peer nodes in the same namespace, allowlisted VPC endpoints, tunnel, and the public internet
• Cross-namespace: blocked by default

All in-cluster traffic between components is encrypted with mTLS via a service mesh.

Service connectivity

Restate environments invoke your service handlers over HTTP. Supported connectivity patterns:

Pattern	How it works
VPC services	Private IP or internal load balancer via VPC endpoints. All traffic stays within the VPC.
FaaS (Lambda)	Invoked via VPC endpoints with IAM authentication. No public internet traversal.
Tunnel	For services in other VPCs or networks. Tunnel clients connect to the BYOC VPC via a VPC endpoint.

Data sovereignty

All customer data remains in your cloud account:

• Invocation payloads, stored state, and snapshots never leave your account
• Application logs are retained in-cluster and accessible to you
• Restate collects only operational metadata (health, resource utilization, environment configuration) for monitoring and management

Audit

Log type	Location	Retention
Kubernetes audit logs	Your CloudWatch / Azure Monitor	Customer-controlled
VPC flow logs	Your S3 / Azure Storage	Customer-controlled
Application logs	In-cluster	Customer-controlled
Control plane operations	Restate audit trail	Per Restate retention policy

Customer controls

Action	Available?	Process
Revoke Restate access	Yes	Remove the Kubernetes bearer token; environments continue running but management is disabled
IP-restrict cluster API	Yes	Configure Kubernetes API server allowlist
Audit management operations	Yes	Kubernetes audit logs capture all control plane actions
Request emergency patching	Yes	File a priority support ticket; Restate SLA applies
Force node replacement	Yes	File a support ticket; completed within SLA