Layer2C System Map

Layer2C is one research system, not a single site. Four public properties each answer a different question about where authority sits in AI infrastructure. This page maps how they fit.

The Four Properties

Canon · Authority

Layer2Cyou are here

Assesses where decision authority sits: 18 AI-infrastructure vendors mapped to the 4+1 Layer AI Infrastructure Model, every component scored with DAPM.

Readiness

Fourth Cloud

Assesses operating-model readiness: on-prem control planes scored function by function against the Fourth Cloud model, FC-0 through FC-4. It identifies gaps; it does not rank vendors.

Validation

Layer2C Labs

Validates where authority actually holds. It puts a slice of the stack on real hardware, real cloud, and real data, then renders a verdict a CTO can act on.

Composition

StackBuilder

Composes reference architectures from the assessed evidence. Deterministic: it reads the graded assessments and never re-grades them.

How They Fit

Layer2C assesses authority: where decision authority sits across the 4+1 Layer AI Infrastructure Model, scored with the Decision Authority Placement Model (DAPM). Fourth Cloud assesses operating-model readiness against the Fourth Cloud model, FC-0 through FC-4. Labs validates where that authority actually holds, through scoped builds on real hardware. StackBuilder composes reference architectures from the assessed evidence.

The short version is Assess, then Validate, then Compose. That tagline is lossy, because it hides a second assessor. Layer2C and Fourth Cloud are parallel instruments, not one stage. One reads vendor authority. The other reads operating-model readiness. Labs then tests the assessments against reality, and StackBuilder composes from what the assessments already establish. StackBuilder never re-grades.

The Shared Spine

Two things run through every property. The first is the 4+1 Layer AI Infrastructure Model: eight layers, from compute and network fabric up through the reasoning plane to the application layer. The second is DAPM, the authority axis. Retained, Delegated, Ceded, or Absent.

Both models put the reasoning plane at the keystone: Layer 2C in the 4+1 model, FC-2C in Fourth Cloud. The two are deliberately not the same shape. They share the DAPM axis and the reasoning-plane keystone, not the layer set. Fourth Cloud scores do not map one to one onto 4+1 layers.

What This System Is Not

Layer2C is an independent architectural research system. Assessments are opinionated analyses, not certifications, paid rankings, procurement recommendations, or permanent conclusions. Labs are funded by sponsorship, but the sponsorship pays for the build, not the verdict. Findings can inform future assessments. They do not purchase them.

For the full policy, read the disclosure, or start with the methodology.