2.6.1. Gigabit Ethernet (GbE) and GbE with IEEE 1588v2
Gigabit Ethernet (GbE) is a high-speed local area network technology that provides data transfer rates of about 1 Gbps. GbE builds on top of the ethernet protocol, but increases speed tenfold over Fast Ethernet. IEEE 802.3 defines GbE as an intermediate (or transition) layer that interfaces various physical media with the media access control (MAC) in a Gigabit Ethernet system. Gigabit Ethernet PHY shields the MAC layer from the specific nature of the underlying medium and is divided into three sub-layers shown in the following figure.
GbE with IEEE 1588v2
GbE with IEEE 1588v2 provides a standard method to synchronize devices on a network with submicrosecond precision. To improve performance, the protocol synchronizes slave clocks to a master clock so that events and time stamps are synchronized in all devices. The protocol enables heterogeneous systems that include clocks of various inherent precision, resolution, and stability to synchronize to a grandmaster clock.
The TX FIFO and RX FIFO are set to register_fifo mode for GbE with IEEE 1588v2.