Ethernet Amendment 7: Media Access Control Parameters, Physical Layers, and Management Parameters for 2.5 Gb/s and 5 Gb/s Operation, Types 2.5GBASE-T and 5GBASE-T
|Publication Date:||22 September 2016|
This clause describes the general requirements for 2.5 Gigabit and 5 Gigabit Ethernet. 2.5 Gigabit Ethernet uses the IEEE 802.3 MAC sublayer operating at a data rate of 2.5 Gb/s, coupled with any IEEE 802.3 2.5GBASE Physical Layer implementation. 5 Gigabit Ethernet uses the IEEE 802.3 MAC sublayer operating at a data rate of 5 Gb/s, coupled with any IEEE 802.3 5GBASE Physical Layer implementation. 2.5 Gb/s and 5 Gb/s Physical Layer entities, such as those specified in Table , provide a bit error ratio (BER) better than or equal to 10-12 at the MAC/PLS service interface.
Gigabit and 5 Gigabit Ethernet are defined for full duplex operation only.
Relationship of 2.5 Gigabit and 5 Gigabit Ethernet to the ISO OSI reference model
Gigabit and 5 Gigabit Ethernet couple the IEEE 802.3 MAC to a family of 2.5 Gb/s and 5 Gb/s Physical Layers. The relationships among 2.5 Gigabit and 5 Gigabit Ethernet, the IEEE 802.3 MAC, and the ISO Open System Interconnection (OSI) reference model are shown in Figure 125-1. While this standard defines interfaces in terms of bits, octets, and frames, implementations may choose other data-path widths for implementation convenience. The only exceptions are as follows:
The XGMII, which, when implemented as a logical interconnection port between the MAC sublayer and the Physical Layer (PHY), uses a 32-bit-wide data path as specified in Clause 46.
The management interface, which, when physically implemented as the MDIO/MDC (Management Data Input/Output and Management Data Clock) at an observable interconnection port, uses a bit wide data path as specified in Clause 45.
The MDI as specified in Clause 126 for 2.5GBASE-T and 5GBASE-T uses a 4 lane data path.