An App Service Plan defines the compute resources for hosting your web apps, APIs, and functions in Azure App Service.
It determines region, VM size, scaling options, and pricing tier.
Multiple apps can share the same ASP.
An App Service Environment is a fully isolated and dedicated environment for securely running App Service apps at high scale.
ASE runs inside your Azure Virtual Network (VNet), giving you network isolation and private IP addresses.
Ideal for high-security and compliance-driven workloads.
- Runs on shared infrastructure managed by Microsoft.
- Deployment is straightforward: choose an ASP tier (Basic, Standard, Premium, Isolated) and deploy your app.
- Apps are exposed via public endpoints unless you configure VNet integration.
- Runs on dedicated infrastructure inside your VNet.
- Deployment requires:
- Creating an ASE (takes longer, more complex).
- Configuring subnets, NSGs, and private DNS.
- Apps in ASE can be fully private (internal ASE) or internet-facing (external ASE).
| Feature | ASP | ASE |
|---|---|---|
| Network Isolation | Limited (via VNet integration) | Full isolation inside VNet |
| Private IP | No | Yes |
| Compliance | Standard Azure compliance | Enhanced compliance for regulated industries |
| Inbound Access | Public by default | Can be private-only |
- Patching & Upgrades: Handled by Microsoft automatically.
- Scaling: Manual or auto-scale based on metrics.
- Maintenance Window: No control; Microsoft manages.
- Patching & Upgrades: Still managed by Microsoft, but you can control maintenance windows.
- Scaling: More complex; requires capacity planning.
- Operational Overhead: Higher due to networking, NSG, and VNet management.
- Transparent updates; minimal downtime.
- No user control over patch timing.
- Updates occur in maintenance windows you define.
- Useful for mission-critical apps that need predictable downtime.
| Aspect | ASP | ASE |
|---|---|---|
| Isolation | Shared | Dedicated in VNet |
| Security | Public by default | Private IP, NSG, full isolation |
| Deployment | Simple | Complex (network setup required) |
| Ops Overhead | Low | High |
| Patching Control | No | Yes |