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IEEE delivers Ethernet-for-cars standard

802.3bw, aka 100BASE-T1, is optimised for wire weight

The march of Ethernet into motor vehicles continues, with the IEEE launching the first automotive standard for 100 Mbps Ethernet over single twisted pair cables.

IEEE 802.3bw, aka 100BASE-T1, is designed to give the auto sector a single homogeneous network architecture, the IEEE says.

The main game for auto applications is to cut down weight. If you take a look at a familiar Cat 5 (or better) cable, you'll count four pairs, and that would make auto wiring harnesses unacceptably heavy.

Bosch senior manager Thomas Hogenmueller, who chaired the 100Base-T1 project, says the standard gets around the weight issue while still delivering enough speed for the industry.

HPE's David Law, who chairs the 802.3 Ethernet Working group, notes that the new standard is “based upon, and is interoperable with, the existing OPEN Alliance BroadR-Reach automotive specification. 100Base-T1, however, is only the first in a family of Ethernet standards to address these application areas, with other projects underway in IEEE 802.3 to develop 1 Gb/s operation and power delivery over a single twisted pair cable, as well as traffic prioritisation.”

BroadR-Reach is a Broadcom-sponsored effort; 100Base-T1 interoperability will mean pre-standard development based on that company's dev kits won't be wasted.

The standard defines the baseband medium for 100Base-T1, as well as the PHY layer specs for point-to-point full duplex 100 Mbps operation. ®

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