Figure 4-12: 1000BASE-X PHY in a GbE OSI Reference Model
OSI Reference
Model Layers
LAN
CSMA/CD Layers
Higher Layers
Application
Presentation
Session
Transport
Network
Data Link
Physical
Reconciliation
1000 Base-X PHY
PCS
GMII
PMA
PMD
LLC
MAC (Optional)
MAC
The transceivers, when configured in GbE functional mode, have built-in circuitry to support the following
PCS and PMA functions, as defined in the IEEE 802.3 specification:
• 8B/10B encoding and decoding
• Synchronization
• Upstream transmitter and local receiver clock frequency compensation (rate matching)
• Clock recovery from the encoded data forwarded by the receiver PMD
• Serialization and deserialization
The transceivers do not have built-in support for other PCS functions, such as the autonegotiation
state machine, collision-detect, and carrier-sense functions. If you require these functions, implement
them in the FPGA fabric or in external circuits.
Note:
Transceiver Protocol Configurations in Cyclone V Devices
Altera Corporation
CV-53004
Gigabit Ethernet
4-12
2013.10.17