Electronics & Connectivity - September 5, 2012 - 8

tech report

Ethernet-based communication follows the ISO OSI layering model and thus allows for reuse and exchangeability on the different protocol levels. layer model nor allow for a switched network. This is different for Ethernet-based communication. requirements that are brought into the car from the outside world. The traditional in-car networking technologies provide a communications bus. As is depicted in the left and middle of the image on page 9, this means that all attached units share the available bandwidth and that adding new units thus affects all existing ones. Modern Ethernet-based networks function via switches (see right side of image). This means that the available bandwidth is not necessarily shared, especially as the topology is not predefined by the technology but can be chosen to suit the specific situation best. Additional flexibility is given because—owing to the layering—different links can have different speed grades (meaning scalability). Adding or changing units does not automatically affect the whole network, but primarily the unit(s) they directly connect to. This means that Ethernet-based communication supports fundamental concepts for a future-proof in-car network.
SAE electronics+connectivity

Layering and switching

Ethernet-based communication follows the ISO OSI layering model and thus allows for reuse and exchangeability on the different protocol levels (see image above). Thus it is possible to use 100-base TX Ethernet, UTSP Ethernet (also known as OPEN Alliance BroadR Reach) and APIX 2 connections in one communication for the physical layer, while maintaining the same MAC protocol, or to include a WLAN (Wi-fi local area network) link, and keeping the same protocols from the IP (Internet protocol) layer up. The use case is not limited, so it does not matter whether the application is diagnostics, driver assistance, infotainment, or something else. This means that Ethernet-based communication is flexible in terms of applications, speed grades, and in terms of

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September 5, 2012



Electronics & Connectivity - September 5, 2012

Table of Contents for the Digital Edition of Electronics & Connectivity - September 5, 2012

Electronics & Connectivity - September 5, 2012
Contents
The Ups and Downs of Connectivity
Tech Report
Securing IT in the sky
Data Collection Made Easy
Ad Index
Resource Links
Upcoming from the Editors
Electronics & Connectivity - September 5, 2012 - Cover1
Electronics & Connectivity - September 5, 2012 - Electronics & Connectivity - September 5, 2012
Electronics & Connectivity - September 5, 2012 - Contents
Electronics & Connectivity - September 5, 2012 - The Ups and Downs of Connectivity
Electronics & Connectivity - September 5, 2012 - Tech Report
Electronics & Connectivity - September 5, 2012 - 5
Electronics & Connectivity - September 5, 2012 - 6
Electronics & Connectivity - September 5, 2012 - 7
Electronics & Connectivity - September 5, 2012 - 8
Electronics & Connectivity - September 5, 2012 - 9
Electronics & Connectivity - September 5, 2012 - 10
Electronics & Connectivity - September 5, 2012 - 11
Electronics & Connectivity - September 5, 2012 - 12
Electronics & Connectivity - September 5, 2012 - 13
Electronics & Connectivity - September 5, 2012 - Securing IT in the sky
Electronics & Connectivity - September 5, 2012 - 15
Electronics & Connectivity - September 5, 2012 - 16
Electronics & Connectivity - September 5, 2012 - 17
Electronics & Connectivity - September 5, 2012 - 18
Electronics & Connectivity - September 5, 2012 - 19
Electronics & Connectivity - September 5, 2012 - Data Collection Made Easy
Electronics & Connectivity - September 5, 2012 - 21
Electronics & Connectivity - September 5, 2012 - 22
Electronics & Connectivity - September 5, 2012 - 23
Electronics & Connectivity - September 5, 2012 - 24
Electronics & Connectivity - September 5, 2012 - Upcoming from the Editors
https://www.nxtbook.com/nxtbooks/sae/12DEC1128
https://www.nxtbook.com/nxtbooks/sae/12DEC0905
https://www.nxtbook.com/nxtbooks/sae/12DEC0530
https://www.nxtbook.com/nxtbooks/sae/12DEC0301
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