Non-Persistence is the Core Design Principle
Imagine a library computer. You sit down, use it for an hour, log out, and the next person gets a completely clean machine — your browsing history, downloads, and open files are gone. AppStream 2.0 works exactly like this, but for any Windows application, streamed to a browser. It is designed for task workers, students, contractors, or kiosk scenarios where users need a specific tool, not a full computer.
- Stateless: When a user logs out, the underlying EC2 instance is terminated. Any file saved to the local
C:drive is permanently lost. This is not a bug — it is the design. It guarantees every user starts with a clean, known-good environment. - Fleets, Not Users: You don't provision individual users; you provision a Fleet — essentially an Auto Scaling Group of identical instances built from a golden image. If 50 students join a class simultaneously, the fleet scales out to 50 instances. When they leave, it scales back to zero. You pay only for active session time.
- Storage Solution: Because the local drive is ephemeral, users must save files to persistent storage. AppStream integrates with: Home Folders (backed by Amazon S3), Google Drive, and OneDrive. When Home Folders are enabled, the user's
Documentsfolder is transparently mapped to S3 — the user saves normally, but the data persists across sessions.
Fleet Types
AppStream offers two fleet types with different cost and latency trade-offs:
- Always-On Fleet: Instances run continuously, even when no users are connected. Sessions start instantly (no cold start). Higher cost because you pay even during idle periods. Best for: business-critical applications where users cannot tolerate startup delays.
- On-Demand Fleet: Instances are started when a user requests a session. Cold start takes 1–2 minutes. Lower cost — you pay only when sessions are active. Best for: scheduled use cases like university labs or training sessions where startup delay is acceptable.
The "SaaS-ification" Pattern
One of the most powerful AppStream use cases is turning legacy desktop applications into browser-delivered SaaS without rewriting them.
Scenario: You are an Independent Software Vendor (ISV) selling a heavy Windows application ("CAD-Pro 98") that requires a 5 GB installer and a specific GPU.
- Old Way: Customer downloads the installer, struggles with dependencies, calls support.
- New Way: Customer logs into your website. You embed an AppStream session in an iframe. They run "CAD-Pro 98" in Chrome instantly — no installation, no hardware requirements, no IT involvement.
The ISV controls the golden image (with the app pre-installed), manages the fleet, and bills customers per session. The customer sees a web app. This pattern is used by companies like Siemens (industrial software) and Autodesk (CAD tools) to modernize legacy desktop software delivery.