Graph API Overview

Overview

Sedna supports mail ingestion and (for select customers) mail egress via the Microsoft Graph API, in addition to traditional forwarding-rule-based ingestion.

• Ingest: Graph API allows Sedna to retrieve messages directly from an Exchange mailbox using a subscription/notification model, with polling fallback to catch missed events. This provides high-volume retrieval, support for larger message sizes, tighter permission control, and better fault tolerance than forwarding rules.
• Egress: Graph API can also be used to send mail out through a customer's Exchange tenant, in place of Sedna's standard outbound mail path.

Sedna's standard pattern is to use one shared, multi-tenant Azure AD App Registration per customer Azure tenant, covering both ingest and egress. This section clarifies how App Registrations work across ingest and egress, and what is/isn't currently supported.

Can we use multiple App Registrations for ingest and egress?

Ingest side: Multiple connections to different Azure tenants are supported — for example, if a customer has more than one Azure tenant, each tenant can have its own App Registration connected to Sedna. Support for multiple App Registrations connected to the same Azure tenant on the ingest side is not supported.

Egress side: Only one Graph Egress connection per Azure tenant is supported. If a customer needs both ingest and egress, we recommend using a single App Registration that covers both flows for that tenant, rather than provisioning separate apps.

Can we use separate App Registrations for ingress vs. egress?

Yes. Sedna does support configuring different App Registrations for ingress and egress flows within the same tenant, if a customer prefers to keep these separated (for example, for permission scoping reasons). This is different from asking for multiple egress App Registrations for the same tenant (see below), which is not supported.

Can we use multiple App Registrations for egress (roadmap)?

Not currently. Sedna's egress integration supports only one Graph Egress Application per tenant today. Supporting multiple egress App Registrations for a single tenant would require net-new development and is not currently planned. Customers with this need should submit a feature request so it can be tracked and prioritised.