A single connection has zero built-in redundancy.
Two connections to the SAME location satisfies neither named model.
1
High Resiliency — 99.9%2 connections, 2 separate DX locations
2
Maximum Resiliency — 99.99%4 connections across 2 locations, 2 devices per location
The AWS Direct Connect Resiliency Toolkit walks you through choosing a named model — not guessing at redundancy yourself.