Infrastructure

What is Tenant Isolation?

Tenant isolation in email ensures that each customer's sending data — suppression lists, analytics, and configurations — are kept separate, preventing one tenant's data from leaking into another's.

Tenant isolation is the principle that each customer (tenant) on a multi-tenant email platform operates independently. Their sending configurations, bounce handling, suppression lists, and delivery metrics are completely separated from every other tenant.

Without data isolation, problems cascade: tenant A's suppression list bleeds into tenant B's sending, analytics get mixed across customers, and webhook events can't be reliably attributed. Data isolation ensures each tenant's email operations are properly scoped.

Tenant isolation typically includes: per-tenant sending domains and DNS records, per-tenant suppression lists (bounces, unsubscribes, complaints), per-tenant analytics and reporting, and per-tenant webhook events. Full IP-level reputation isolation (dedicated IPs per tenant) is a separate, more advanced capability that requires dedicated IP infrastructure.

Why Tenant Isolation Matters

Without proper tenant isolation, data leaks between customers: suppression lists get mixed up, analytics show the wrong data, and it becomes impossible to scope sending operations per customer. For platforms that manage many customers, proper data isolation is table stakes.

How Ark Handles Tenant Isolation

Ark scopes all data by tenant. Each tenant has their own domains, suppression lists, analytics, and webhook events. Every API call is scoped to a tenant ID, ensuring clean data separation between customers.

Frequently Asked Questions