V0.1 | 2016-09-05

8. Vector Congress – Nov. 30th 2016

Ethernet Basic Software – What’s next?

2

The dissemination of Automotive Ethernet increases

The use cases evolve High-speed diagnostic access (DoIP) Smart Charging (V2G) In-Vehicle Ethernet

> Stream data (AVB, RTP, etc.) > Control data (SOME/IP, Multi-PDU)

What’s next? Reliable control data with Time-Sensitive Networking Automotive Ethernet in POSIX-based systems Dynamic use of service-oriented communication

Introduction – Automotive Ethernet

0%50%

100%150%200%250%300%350%400%

2008 2009 2010 2011 2012 2013 2014 2015 2016

Ethernet: Growth rate (Basis: orders 2013 = 100%)

3

2

Time-Sensitive Networking (TSN)

Automotive Ethernet in POSIX-Based Systems

1

3 Service-Oriented Communication

4

ECU µC

Switch

ECU

Motivation Time-Sensitive Networking

Traffic convergence must be handled Control data Streaming data

Diverging transmission behavior & requirements

ECU ECU ECU

Switc

h

ECU

ECU

µC

Complex topology Independent, full-duplex links Several hops within one cluster Frame duplication (multi- and broadcast) Congestion at egress ports

Complex timing & load analysis compared to CAN

5

ECU

Motivation Time-Sensitive Networking

Traffic convergence must be handled Control data Streaming data

Diverging transmission behavior & requirements

Complex topology Independent, full-duplex links Several hops within one cluster Frame duplication (multi- and broadcast) Congestion at egress ports

Complex timing & load analysis compared to CAN

TSN provides mechanisms to target this: Some of which focus on the egress port and are based on existing standards (e.g.

VLAN, QoS).

µC

Switch

ECU ECU ECU

ECU

Switc

h

ECU

ECU

…

Prio 0

Prio 1

Prio 6

Prio 7

Scheduler

Link

µC

Shaper

Shaper

6

What is AVB? A set of IEEE standards Provided by the AVB task group Predecessor of TSN (until Nov. 2012) A toolbox

What are AVB’s main components? Credit based traffic shaper (FQTSS) Time synchronization (gPTP) Stream reservation (SRP) Transport Protocol (AVTP)

What can be done with AVB? Provide latency guarantees Provide bandwidth guarantees Synchronize nodes and data

The Predecessor - Audio Video Bridging (AVB) Time-Sensitive Networking

Src

Src

Src

Ctrl Ctrl

Dst

Dst

Dst

correlate inputs concert outputs

t t

t

without shaping

with shaping

Prio 0

Prio 1 Sched.

Link

FQTSS

reduce bursts

7

What is TSN? Extension of the AVB toolbox AVB focus: Streaming with real time guarantees TSN focus: Reliable control data with hard real time

guarantees Is partly still under discussion

What are TSN’s main components? Time-aware shaper (TDMA) Frame preemption Ingress policing Fault tolerant clocks Redundant communication

What can be done with TSN? Achieve stricter timing requirements Increase reliability through redundancy

Time Sensitive Networking (TSN) Time-Sensitive Networking

latency

reliability

t

Sched

Link FQTSS

TAS*

scheduled time slots

*TAS – Time-aware shaper

t

t t t

Prio 0

Prio 1

Prio 2

guard band

8

µController

Which Basic-Software modules are impacted by AVB and TSN

Impact on Basic-Software Time-Sensitive Networking

Ethernet Controller (MAC)

Ethernet Driver

IP AvTp AVB/TSN Protocols

UDP TCP

gPTP

SPI

Switch Driver

Switch

Standard Stack The standard Ethernet stack is

mostly unaffected AVB/TSN is designed for

interoperability AVB/TSN protocols have

dedicated EtherTypes

AV Transport Protocol The AVTP protocol is lower

layer to media applications It supports media

synchronization mechanisms, e.g. presentation time

AVB/TSN Protocols There is a set of other

protocols in the AVB/TSN world

They are mostly for dynamically setting up the network

gPTP gPTP provides time

synchronization It benefits from

hardware timestamping

Hardware Related Modules The hardware-related parts are

most affected Switch + Switch Driver MAC + Ethernet Driver

AVB/TSN-related features QoS FQTSS shaper Time-aware shaper Hardware timestamping Ingress policing

9

2

Time-Sensitive Networking (TSN)

Automotive Ethernet in POSIX-Based Systems

1

3 Service-Oriented Communication

10

POSIX-based operating systems, especially Linux, provide: Support for high performance CPUs Support for dynamic programming and configuration Rich set of existing features (connectivity, infotainment, image recognition, …)

POSIX-based systems are on the advance

But automotive ECUs require automotive-specific features Configuration Diagnostics Network Management Communication

These are not included in the standard feature set of a POSIX-based system

This is also true for Automotive Ethernet!

Motivation Automotive Ethernet in POSIX-based Systems

11

What automotive-specific Ethernet functions are there? Automotive Ethernet in POSIX-based Systems

Automotive Ethernet Stack

Ethernet Controller (MAC)

Ethernet Driver

IP AVB/TSN Modules

UDP TCP

SPI

Switch Driver

SoAd

DoIP UdpNm SOME/IP

Kernel-Mode Modules User-Mode Modules

Ethernet Driver It should support the required hardware-related features It runs in kernel-mode, extending it is difficult

Switch Driver Is specific to typical automotive switches Can be added as separate user mode component

Standard Modules (ARP, IP, TCP, UDP, etc.) Standard components can typically be used Configuration parameters may differ (e.g. timeout times)

AVB/TSN Modules (AvTp, SRP, BMCA, etc.) Specific, but not automotive-specific Can be added as user-mode modules

(if hardware-related features are provided)

Socket Adapter (SoAd) Is not per se necessary Multi-PDU feature is most-likely needed

Diagnostics over IP (DoIP) Required if ECU is directly accessible via tester

Network Management (UdpNm) Allows ECU is to participate in network management May include partial networking

Service-oriented Middleware (SOME/IP) Data serialization Service discovery

12

Steps towards a native POSIX implementation Automotive Ethernet in POSIX-based Systems

MCU 1 MCU 2 AUTOSAR POSIX

IPC IPC

SPI/USB/ETH

MCU AUTOSAR POSIX

IPC IPC

Shared Memory

Hypervisor

MCU POSIX

Application AUTOSAR

IPC IPC

MCUc POSIX

Application Application

Native POSIX Implementation AUTOSAR as a Process

AUTOSAR as a Guest AUTOSAR as a Companion

ECU ECU

ECU ECU

Segregation

Integration

vs.

Operating System

Shared Memory

Automotive Middleware

13

2

Time-Sensitive Networking (TSN)

Automotive Ethernet in POSIX-Based Systems

1

3 Service-Oriented Communication

14

Goals of a Service-Oriented Architecture (SOA) Loosen the coupling between interacting devices while maintaining their interoperability. Reduce broadcasting (compared to CAN or FlexRay)

Motivation Service-Oriented Communication

Components of a SOA

Service Discovery Offering, finding and subscribing to services

Addressing Addressing of clients, servers and services

Service Description Describing the capabilities of devices and how to use them

Method Invocation Invoking methods on the server

Events Subscribe for automatic change notifications

Ressources on most ECUs are highly limited

SOME/IP is statically used today Services are predefined Service description is shared via a design-time exchange format (e.g. .arxml) Service usage, however, is dynamic

15

Upcoming E/E-Architectures provide more ressources (POSIX-based ECUs)

Are there automotive use cases that require a dynamic service-oriented architecture?

Dynamic use of service-oriented communication Service-Oriented Communication

Additional challenges System behavior becomes less deterministic Testability is reduced Potential surface area for attacks

Adding new Services via Cloud or OTA update Reducing change impact

High Performance ECU

Server

Server Server

Client Server

Client

High Performance ECU

S2S* Gateway dbc

Client Client Client

Service-Oriented Communication Service-Oriented Communication

Cloud

driver

*S2S – Signal-to-Service

CAN/LIN/FlexRay/Eth PDU

16 © 2016. Vector Informatik GmbH. All rights reserved. Any distribution or copying is subject to prior written approval by Vector. V0.1 | 2016-09-05

For more information about Vector and our products please visit www.vector.com

Author: Zimmer, Bastian Vector Germany