# NVLink Fusion

In this technical article, NVIDIA explains how NVLink 6 supports large-scale AI factories through a multi-layer resiliency framework spanning the physical, link, application, and system layers: the physical layer combines lightweight FEC with Physical Layer Retry (PLR) and UPHY recovery for a natively lossless fabric, the link layer uses credit-based flow control (CBFC) to eliminate packet drops by design, and the application layer uses Dynamo Shadow Engine Recovery and checkpointing to shorten interruptions, with the article reporting that in benchmarked deployments on B200 GPUs shadow engine recovery reduced inference downtime from 283 seconds to 7.3 seconds.

In this technical article, NVIDIA explains how NVLink 6 supports large-scale AI factories through a multi-layer resiliency framework spanning the physical, link, application, and system layers: the physical layer combines lightweight FEC with Physical Layer Retry (PLR) and UPHY recovery for a natively lossless fabric, the link layer uses credit-based flow control (CBFC) to eliminate packet drops by design, and the application layer uses Dynamo Shadow Engine Recovery and checkpointing to shorten interruptions, with the article reporting that in benchmarked deployments on B200 GPUs shadow engine recovery reduced inference downtime from 283 seconds to 7.3 seconds.