jschoubben
b1874f1d0f
Asked whether a real setup is coverable — router, modem, access points — the answer splits, and one part was a genuine gap. Most equipment is invisible and the omission is deliberate. The test: does the device change what an IP packet can do? A switch moves frames within a segment. An access point bridges wireless clients onto one — a machine on wifi and a machine on cable are the same machine to IP. A controller configures equipment and has no packets of its own. Modelling any of them adds a fixture with no fault to catch. Two entries in that list do matter. A modem in bridge mode is a media converter and invisible; in router mode it is a second gateway, which is double NAT — expressible as nested segments, but publishing through two gateways still is not, and that is now named as the one real absence. And VLANs are segments, which exposed the gap: inter-segment policy was inexpressible. inbound: is a HOST firewall, per machine. A segmented router enforcing rules between networks is a different thing and blocks traffic regardless of what the destination thinks — a node behind such a rule cannot be reached even by a peer that knows exactly where it is. policy: states it as a fact about a pair rather than a property of either, defaulting to allowed and asymmetric by design, because the useful configuration is almost always one-directional. Segments may also share a gateway: identical gateway declarations mean one gateway machine, not two, because that is what a VLAN-capable router is — and two routers sharing an address would not work anyway.
03-DESIGN / 01-to-be
The mesh being built toward. Every statement here traces to a record in
02-DECISIONS/; nothing arrives by drafting.
A document here describes an intention. What currently runs is in
00-as-is/, and the two are never merged — when something ships, the as-is
document is written and this one's status becomes implemented.
| Document | Covers | Rests on |
|---|---|---|
00-work-breakdown.md |
How the decomposition gets built, in what order, and where a human must look | ADR 0015 |
01-end-to-end-testing.md |
The lab: a real mesh a change can be run against before it reaches nodes | ADR 0016, 0029 |
02-scenario-declaration.md |
What a scenario declares — the underlay, and what to place on it | ADR 0031 |
Not yet written
- The eight bounded contexts. ADR 0015 decides the decomposition; the per-context specifications do not exist yet. The work breakdown says in what order they are needed.
- Domain grouping outside the core. ADR 0017 settles the principle and explicitly does not settle the domain list. That is a research effort, not a design document, until it concludes.