# Catalyst hosting
Diagrid Catalyst is built on the open-source [Dapr](https://dapr.io/) runtime and centralizes the Dapr deployment in a Kubernetes cluster — operated by Diagrid or by you — where it runs as a managed platform. Your applications connect to the Catalyst data plane, which handles workflow execution, state management, and distributed-application coordination, independently of where those applications run.
## Deployment models
Catalyst has four deployment models, from a fully managed cloud service to a fully air-gapped deployment. They differ in **where the Catalyst data plane runs** and **who operates it**:
| Deployment model | Control plane | Data plane | Operated by | Best for |
|------------------|---------------|------------|-------------|----------|
| [**Catalyst Cloud**](https://docs.diagrid.io/operate/hosting/catalyst-cloud) | Diagrid | Diagrid, multi-tenant | Diagrid | Evaluation and small-to-medium workloads, with zero setup. |
| [**Dedicated Cloud**](https://docs.diagrid.io/operate/hosting/dedicated-cloud) | Diagrid | Diagrid, single-tenant | Diagrid | Production workloads that need single-tenant isolation without operating infrastructure. |
| [**BYOC**](https://docs.diagrid.io/operate/hosting/byoc) | Diagrid | Your cloud | Diagrid or you | Data residency — application data must stay in your own network. |
| [**Enterprise Server**](https://docs.diagrid.io/operate/hosting/enterprise-server) | You | You | You | Regulated and defense environments with no external connectivity. |
[BYOC](https://docs.diagrid.io/operate/hosting/byoc) comes in two flavors: **[managed](https://docs.diagrid.io/operate/hosting/byoc/managed)**, where Diagrid provisions and operates the region inside your cloud account, and **[self-managed](https://docs.diagrid.io/operate/hosting/enterprise-self-hosted)**, where you deploy and operate the data plane on your own Kubernetes cluster.
Catalyst Cloud is available on a free plan; the other three models are part of Catalyst Enterprise. See [Plans & support](https://docs.diagrid.io/operate/plans-and-support).
Within any model, Catalyst isolates workloads using [regions](https://docs.diagrid.io/operate/platform-operations/regions) — data-plane clusters — and [projects](https://docs.diagrid.io/operate/platform-operations/projects), logical groups within a region. For [multi-region high availability](https://docs.diagrid.io/operate/platform-operations/multi-region), regions can also be joined into a region group, which runs one project across several regions so that it survives the loss of any one of them.
The diagrams below show where the control plane, the data plane (Dapr deployment plus Catalyst agent), and your applications run in each model.
### Catalyst Cloud
A shared, Diagrid-hosted control and data plane. Your applications connect over the public internet. Best for evaluation and small-to-medium development workloads.
```mermaid
---
title: Catalyst Cloud
---
flowchart LR
subgraph Diagrid["Diagrid hosted
Multi-tenant deployment"]
direction LR
CP("Catalyst
control plane")
subgraph DP["Catalyst data plane"]
direction LR
DAPR("Dapr
deployment")
AGENT("Catalyst
agent")
end
CP<-->DP
DAPR ~~~ AGENT
end
subgraph Customer["Your environment"]
subgraph APPS["Your apps & agents"]
direction TB
C(Containers):::customerNode
VM(Virtual Machines):::customerNode
PM(Physical Machines):::customerNode
SL(Serverless):::customerNode
C ~~~ PM
VM ~~~ SL
end
end
DP<--"Internet"-->APPS
style Diagrid stroke:#22613f,stroke-width:2px
style Customer stroke:#ed8936,stroke-width:2px
style DP stroke-dasharray:0,stroke-width:1.5px
classDef customerNode stroke:#ed8936,stroke-width:2px
```
### Dedicated Cloud
A dedicated, single-tenant control and data plane managed by Diagrid. The topology mirrors Catalyst Cloud, but the platform is isolated to one customer and sized for production workloads. See [Catalyst Dedicated Cloud](https://docs.diagrid.io/operate/hosting/dedicated-cloud) for how to create one.
```mermaid
---
title: "Catalyst Dedicated Cloud"
---
flowchart LR
subgraph Diagrid["Diagrid hosted
Single-tenant deployment"]
direction LR
CP("Catalyst
control plane")
subgraph DP["Catalyst data plane"]
direction LR
DAPR("Dapr
deployment")
AGENT("Catalyst
agent")
end
CP<-->DP
DAPR ~~~ AGENT
end
subgraph Customer["Your environment"]
subgraph APPS["Your apps & agents"]
direction TB
C(Containers):::customerNode
VM(Virtual Machines):::customerNode
PM(Physical Machines):::customerNode
SL(Serverless):::customerNode
C ~~~ PM
VM ~~~ SL
end
end
DP<--"Internet"-->APPS
style Diagrid stroke:#22613f,stroke-width:2px
style Customer stroke:#ed8936,stroke-width:2px
style DP stroke-dasharray:0,stroke-width:1.5px
classDef customerNode stroke:#ed8936,stroke-width:2px
```
### BYOC: Managed
Diagrid manages the control plane and provisions and operates the data plane inside your own cloud account, through a [cloud connection](https://docs.diagrid.io/operate/hosting/byoc/managed) you grant. Application traffic and data stay in your network, while Diagrid keeps operational responsibility for the region.
```mermaid
---
title: "Catalyst BYOC: Managed"
---
flowchart LR
subgraph Diagrid["Diagrid hosted"]
CP("Catalyst
control plane")
end
subgraph Customer["Your cloud account & network"]
direction LR
subgraph DP["Catalyst data plane
Provisioned & operated by Diagrid"]
direction LR
DAPR("Dapr
deployment")
AGENT("Catalyst
agent")
end
subgraph APPS["Your apps & agents"]
direction TB
C(Containers):::customerNode
VM(Virtual Machines):::customerNode
PM(Physical Machines):::customerNode
SL(Serverless):::customerNode
C ~~~ PM
VM ~~~ SL
end
DAPR ~~~ AGENT
DP<-->APPS
end
CP<-->DP
style Diagrid stroke:#22613f,stroke-width:2px
style Customer stroke:#ed8936,stroke-width:2px
style DP stroke:#22613f,stroke-dasharray:0,stroke-width:1.5px
classDef customerNode stroke:#ed8936,stroke-width:2px
```
### BYOC: Self-managed
Diagrid manages the control plane; the data plane runs inside your infrastructure, deployed and operated by you. Applications connect to the data plane over your private network, keeping application traffic and data local. See [Self-managed BYOC](https://docs.diagrid.io/operate/hosting/enterprise-self-hosted) for the full deployment workflow.
```mermaid
---
title: "Catalyst BYOC: Self-managed"
---
flowchart LR
subgraph Diagrid["Diagrid hosted"]
CP("Catalyst
control plane")
end
subgraph Customer["Your infrastructure & network"]
direction LR
subgraph DP["Catalyst data plane"]
direction LR
DAPR("Dapr
deployment")
AGENT("Catalyst
agent")
end
subgraph APPS["Your apps & agents"]
direction TB
C(Containers):::customerNode
VM(Virtual Machines):::customerNode
PM(Physical Machines):::customerNode
SL(Serverless):::customerNode
C ~~~ PM
VM ~~~ SL
end
DAPR ~~~ AGENT
DP<-->APPS
end
CP<-->DP
style Diagrid stroke:#22613f,stroke-width:2px
style Customer stroke:#ed8936,stroke-width:2px
style DP stroke-dasharray:0,stroke-width:1.5px
classDef customerNode stroke:#ed8936,stroke-width:2px
```
### Enterprise Server
Both the control plane and the data plane run inside your infrastructure. No traffic leaves your network, which suits environments with strict regulatory or network isolation requirements. See [Catalyst Enterprise Server](https://docs.diagrid.io/operate/hosting/enterprise-server).
```mermaid
---
title: "Catalyst Enterprise Server"
---
flowchart LR
subgraph Customer["Your infrastructure & network"]
direction LR
CP("Catalyst
control plane")
subgraph DP["Catalyst data plane"]
direction LR
DAPR("Dapr
deployment")
AGENT("Catalyst
agent")
end
subgraph APPS["Your apps & agents"]
direction TB
C(Containers):::customerNode
VM(Virtual Machines):::customerNode
PM(Physical Machines):::customerNode
SL(Serverless):::customerNode
C ~~~ PM
VM ~~~ SL
end
DAPR ~~~ AGENT
CP<-->DP
DP<-->APPS
end
style Customer stroke:#ed8936,stroke-width:2px
style DP stroke-dasharray:0,stroke-width:1.5px
classDef customerNode stroke:#ed8936,stroke-width:2px
```