Circumventing the CAP Theorem with Open Atomic Ethernet

TL;DR

Open Atomic Ethernet (OAE) introduces a new network paradigm that reduces the impact of network partitions on distributed systems by enabling rapid detection and healing of fabric faults, challenging traditional CAP theorem constraints.

Contribution

The paper proposes Open Atomic Ethernet, which shifts the engineering regime by implementing bounded-time bilateral reconciliation and a mesh topology to mitigate CAP tradeoffs.

Findings

Reduces frequency and duration of soft partitions

Enables nanosecond-scale fault detection and healing

Provides a new perspective on CAP theorem applicability

Abstract

The CAP theorem is routinely treated as a systems law: under network partition, a replicated service must sacrifice either consistency or availability. The theorem is correct within its standard asynchronous network model, but operational practice depends on where partition-like phenomena become observable and on how lower layers discard or preserve semantic information about message fate. This paper argues that Open Atomic Ethernet (OAE) shifts the engineering regime in which CAP tradeoffs become application-visible by (i) replacing fire-and-forget link semantics with bounded-time bilateral reconciliation of endpoint state -- the property we call bisynchrony -- and (ii) avoiding Clos funnel points via an octavalent mesh in which each node can act as the root of a locally repaired spanning tree. The result is not the elimination of hard graph cuts, but a drastic reduction in the frequency and duration of application-visible "soft partitions" by detecting and healing dominant fabric faults within hundreds of nanoseconds. We connect this view to Brewer's original CAP framing, the formalization by Gilbert and Lynch, the CAL theorem of Lee et al., which replaces binary partition tolerance with a quantitative measure of apparent latency, and Abadi's PACELC extension.