osi layers in automotive networks -...
TRANSCRIPT
OSI Layers in Automotive Networks
1
OSI Layers in Automotive Networks 2013-03-20
IEEE 802.1 Plenary Meeting - Orlando
Aboubacar Diarra, Robert Bosch GmbH
2013-03-20 - IEEE 802.1 Plenary Meeting - Orlando
OSI Layers in Automotive Networks
2
Outline
OSI Reference Model
Simplified generic Architecture for Automotive Serial Busses
Basic Automotive E/E Architecture
Automotive Bus Systems in the OSI Model
Ethernet Impact on Automotive Bus Layering
2013-03-20 - IEEE 802.1 Plenary Meeting - Orlando
OSI Layers in Automotive Networks
3
OSI Reference Model
7 Application
6 Presentation
5 Session
4 Transport
3 Network
2 Data Link
1 Physical
Application A
7 Application
6 Presentation
5 Session
4 Transport
3 Network
2 Data Link
1 Physical
Application B
Transmission Medium
Data
Application Protocol
Communication Protocol
Bit Transmission Protocol
3 relevant Layers for
Automotive Control Data
Communication with Area
Busses: Layers 1, 2 and 7
ECU 1 ECU 2
2013-03-20 - IEEE 802.1 Plenary Meeting - Orlando
OSI Layers in Automotive Networks
4
Simplified generic Architecture for Automotive
Serial Busses
Bus Node
Communication
Application
Communication
Controller
Transceiver
Bus Node
Communication
Application
Communication
Controller
Transceiver
Communication Protocol
Physical Layer Definition
BUS
Layer 7
Layer 1, 2
Layer 1
2013-03-20 - IEEE 802.1 Plenary Meeting - Orlando
Layer 1, 2, 4*
OSI Layers in Automotive Networks
5
Basic Automotive E/E Architecture
Central
Gateway
LIN High
speed
CAN
FlexRay CAN
MOST
Layer 1 to 7
Layer 4 *
Diagnosis
over CAN
* Layer 4 is used in this case for Diagnosis Services
Layer 1, 2, 4* Layer 1, 2, 4*
2013-03-20 - IEEE 802.1 Plenary Meeting - Orlando
OSI Layers in Automotive Networks
6
Automotive Bus Systems in the OSI Model:
Example of the CAN Bus
7 Application
6 Presentation
5 Session
4 Transport
3 Network
2 Data Link
1 Physical
Logical Link Control (LLC) Acceptance Filtering
Overload Notification
Recovery Management
Medium Access control(MAC) Data Encapsulation/Decapsulation
Frame Coding
Error Detection/Signaling/Handling
Physical Signaling (PLS)
Bit Encoding/Decoding
Bit Time Synchronization
Physical Medium attachment(PMA) Driver/Receiver Characteristics
Media Dependant Interface(MDI) Connectors
2013-03-20 - IEEE 802.1 Plenary Meeting - Orlando
OSI Layers in Automotive Networks
7
Automotive Bus Systems in the OSI Model:
Example of the FlexRay Bus
7 Application
6 Presentation
5 Session
4 Transport
3 Network
2 Data Link
1 Physical
Logical Link Control (LLC) Protocol Operation Control
Medium Access control(MAC) Message Framing
Communication Cycle
Physical Signaling (PLS) Bit Encoding/Decoding
Bit Time Synchronization
Physical Medium attachment(PMA) Driver/Receiver Characteristics
Media Dependant Interface(MDI) Connectors
2013-03-20 - IEEE 802.1 Plenary Meeting - Orlando
OSI Layers in Automotive Networks
8
Automotive Bus Systems in the OSI Model:
Example of the MOST Bus
7 Application
6 Presentation
5 Session
4 Transport
3 Network
2 Data Link
1 Physical
Application Programming Interface
Netservices Layer 2
Netservices Layer 1
MOST Transceiver
Electrical PHY, FOT’s Connectors and Plastic Fiber
2013-03-20 - IEEE 802.1 Plenary Meeting - Orlando
Layer 2
OSI Layers in Automotive Networks
9
Ethernet Impact on Automotive Bus Layering:
Example of On-Board Communication *
Central
Gateway
LIN High
speed
CAN
FlexRay CAN
Switch
Ethernet
Remark:
Layer 3 and 4 can be
solicited for Car2X
Communication
Applications.
* Excepted On-Board Diagnosis (OBD)
which needs a Layer 4 support
2013-03-20 - IEEE 802.1 Plenary Meeting - Orlando
OSI Layers in Automotive Networks
10
Ethernet Impact on Automotive Bus Layering:
Example of Off-Board Communication
Central
Gateway
LIN High
speed
CAN
FlexRay CAN
Layer 4
Layer 3 / 4 Diagnosis
over IP (DoIP)
Switch
Ethernet
Layer 3 / 4
2013-03-20 - IEEE 802.1 Plenary Meeting - Orlando
OSI Layers in Automotive Networks
11
Conclusion(1)
In reference to the OSI Data Communication Model, the Serial Interface
of CAN, FlexRay and LIN Busses typically needs 3 OSI Layers for On-
Board Communication excepted OBD: the Physical Layer, the Data
Link Layer and the Application Layer
The MOST Bus covers all the 7 OSI Layers for On-Board Communication
The Transport Layer is used for Off-Board Communication like
Diagnosis and also for OBD on these typical Automotive Area Networks.
The Layers 3 and 4 can be used for Vehicle On-Board Communication in
Car2X Communication Applications
2013-03-20 - IEEE 802.1 Plenary Meeting - Orlando
OSI Layers in Automotive Networks
12
Conclusion(2)
Therefore, for a Control Data Communication that occurs in an In-
vehicle closed Network, the need of the Layer 2 is justified.
On top of that, Layer 3 Routing Processes require more infrastructure
(eg. IP stack implementation, software implementation, memory need . .
.) and costs investments than Layer 2 solutions from an Automotive
Perspective
For In-vehicle Control Applications which require a very low Latency, a
Layer 2 solution is more pragmatic than a Layer 3 solution
However, Diagnosis over IP, Car2X and In-Car Wireless Communication
Applications need Layer 3 Routing Support
2013-03-20 - IEEE 802.1 Plenary Meeting - Orlando
OSI Layers in Automotive Networks
13
Thank You for your Attention
2013-03-20 - IEEE 802.1 Plenary Meeting - Orlando