CX82100 Home Network Processor Data Sheet
7
Ethernet Media Access Control Interface Description
The HNP implements the Ethernet Media Access Control (EMAC) as defined in
Reference [4]. Also implemented is the MII interface to the physical layer as defined in
Reference [5].
In the OSI reference model as shown in Figure 7-1, the lowest layer is Physical and the
next layer up is Data Link. The Data Link layer is segmented into 2 parts, Medium
Access Control (MAC) which interfaces to the PHY, and the Logical Link Control (LLC)
which interfaces to the MAC and to higher layers.
Figure 7-1. MAC Sublayer Partition, Relationship to OSI Reference Model
LAN CSMA/CD Layers
OSI Reference Model
Layers
Higher Layers
Application
Presentation
Session
LLC - Logical Link Control
MAC - Media Access Control
PLS
Reconciliation
Reconciliation
Transport
Network
MII
AUI
MDI
MII
PLS
PLS
PMA
PMD
Data Link
Physical
PMA
PMA
MDI
Medium
Medium
Medium
AUI = Attachment Unit Interface
MDI = Medium Dependent Interface
MII = Media Independent Interface
PLS = Physical Layer Signaling
PMA = Physical Medium Attachment
PMD = Physical Medium Dependent
1 Mb/s, 10 Mb/s
10 Mb/s
100 Mb/s
101545_028
The LLC together with the MAC must provide the following Data Link functionality:
•
Data Encapsulation (transmit and receive)
−
−
Framing (frame boundary delimitation, frame synchronization)
Addressing (handling of source and destination addresses)
•
Error detection (detection of physical medium transmission errors)
−
−
−
Media Access Management
Medium Allocation (collision avoidance)
Contention Resolution (collision handling)
101306C
Conexant Proprietary and Confidential Information
7-1
CONEXANT [ CONEXANT SYSTEMS, INC ]
