Transparent Bridge Ethernet Switches for Sub-Microsecond Synchronization

The patent segments the switching function into two distinct parts: a transparent bridge function that forwards frames without store-and-forward delay, and a separate error checking mechanism that validates frames. This segmentation allows the system to maintain deterministic data delivery through the bridge while separately handling error propagation prevention, thus resolving the contradiction between reliability and time loss.

The patent introduces transparent bridges as intermediary devices that forward time synchronization frames without introducing significant delay or jitter. These bridges act as mediators that extend network coverage while maintaining synchronization precision by passing timing information transparently through the network, thus resolving the contradiction between network coverage extension and synchronization precision maintenance.

The patent replaces the mechanical CSMA/CD collision detection mechanism of half-duplex Ethernet with a transparent bridge forwarding mechanism that operates in full-duplex mode. This substitution eliminates collisions by using dedicated transmit and receive paths while maintaining the simplified daisy-chain topology, thus resolving the contradiction between wiring simplicity and data throughput.

The patent applies different quality characteristics to different switching functions: the transparent bridge function uses minimal processing with no store-and-forward delay to maintain time synchronization precision, while error checking functions operate separately with full processing capability. This local quality differentiation allows full-duplex Ethernet to achieve high throughput while transparent bridges maintain sub-microsecond synchronization precision.