cx82100 Conexant Systems, Inc., cx82100 Datasheet - Page 99

• Manufacturer Part Number: cx82100
• Description: Home Network Processor Hnp
• Manufacturer: Conexant Systems, Inc.

7
Figure 7-1. MAC Sublayer Partition, Relationship to OSI Reference Model
101306C
OSI Reference M odel
AUI = Attachm ent Unit Interface
MDI = Medium Dependent Interface
MII = Media Independent Interface
PLS = Physical Layer Signaling
PMA = Physical Medium Attachm ent
PMD = Physical Medium Dependent
Presentation
Application
Transport
Data Link
Physical
Session
Network
Layers
Ethernet Media Access Control Interface Description
Conexant Proprietary and Confidential Information
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.
The LLC together with the MAC must provide the following Data Link functionality:
•
•
Data Encapsulation (transmit and receive)
−
−
Error detection (detection of physical medium transmission errors)
−
−
−
CX82100 Home Network Processor Data Sheet
Framing (frame boundary delimitation, frame synchronization)
Addressing (handling of source and destination addresses)
Media Access Management
Medium Allocation (collision avoidance)
Contention Resolution (collision handling)
1 Mb/s, 10 Mb/s
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Medium
PMA
PLS
M AC - M edia Access Control
LLC - Logical Link Control
LAN CSM A/CD Layers
MDI
AUI
MII
Higher Layers
Reconciliation
10 Mb/s
Medium
PMA
PLS
MDI
MII
Reconciliation
100 Mb/s
Medium
PMA
PMD
PLS
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