2.1 KiB
2.1 KiB
ADR-0002 · Tier hierarchy: Router / Cell / Core / Hub
Status: accepted Date: 2026-05
Context
The platform is distributed across multiple physical components. Without a clear naming convention, conversations devolved into ambiguous terms ("the box", "the gateway", "the brain"). We needed a vocabulary that:
- Reflects the actual physical/logical separation.
- Scales from minimal deployments (one site, few cameras) to large fleets.
- Is brandable and can be used in marketing without sounding generic.
Decision
Four tiers, named:
| Tier | Name | Hardware | Role |
|---|---|---|---|
| 0 | Blocao Router | OpenWrt-class device (e.g. GL.iNet GL-MT6000) | Gateway, broker, console host, GitOps reconciler |
| 1 | Blocao Cell | RK3588 SBC (e.g. Banana Pi BPI-W3) | Edge AI inference, recording, forensic API |
| 2 | Blocao Core | Jetson Orin NX or similar | Multi-Cell coordinator, heavier models. Optional |
| 3 | Blocao Hub | EU sovereign bare-metal (Hetzner Falkenstein/Helsinki) | Multi-site control plane, fleet management |
Topology notation: R+1 (router + 1 Cell), R+3+C (router + 3 Cells + 1 Core), R+0 (router only, no edge AI yet).
Sites are identified as BL-<slug> (e.g. BL-LAB, BL-WAREHOUSE-N).
Consequences
Good:
- Each name is short, brandable, and used as-is in product literature.
- "Router + Cell + Core" follows a biological metaphor (smallest → larger units of integration) that customers grasp quickly.
- Hub is clearly remote, separating it from on-site components.
Bad / trade-offs:
- "Cell" can be confused with "cellular" (mobile networks). We accept this — context disambiguates, and "blocao cell" + "LTE failover" don't appear together often enough to confuse.
- Customers occasionally call the Cell "the AI box". We don't correct it in early conversations; the official term sticks once they read docs.
Alternatives considered
- Edge / Gateway / Coordinator / Cloud: too generic, can't be branded.
- Node / Hub / Core / Cloud: "node" is overused, "cloud" we explicitly reject.
- Brain / Spine / Eye / Memory (biological): too cute for industrial buyers.