What is the difference between push and pull architecture?

Question

Accepted Answer

**Push** — data sent to consumers. **Pull** — consumers request data.

**Push Architecture:**
- Server sends data to clients.
- Real-time updates.
- More server resources.
- WebSocket, Server-Sent Events.

```
Push:
Client ← Server pushes data
Examples: Chat, Live notifications
WebSocket connection maintained
```

**Pull Architecture:**
- Clients request data from server.
- On-demand updates.
- More client resources.
- REST, Polling.

```
Pull:
Client → Requests data → Server
Examples: REST API, Web pages
Client decides when to fetch
```

**Key differences:**
- **Push** — server-initiated.
- **Pull** — client-initiated.
- **Push** — real-time.
- **Pull** — on-demand.

Systems Analyst: What is the difference between push and pull architecture?