@chanj, make no mistake. HD front, rear and side cameras featured in a car will be driving this, for safety applications. In fact, the high-bandwidth demand for automotive is real and even more paramount, because autmotive companies don't even want to "compress" the video streams captured by HD cameras!
Excellent point. Multiple small switches might provide better fault tolerant than 1 big interconnected switch. Daisy-chain is probably not a very good idea for sure. Will In-Vehicle-Network open up new opportunity of routing technology?
"safety demands are paramount, a long product development cycle is a given" captures the main roadblock of in-vehicle-network.
Looking at it from the angle, if a safety feature which demands high-bandwidth communication is getting a lot of attention from consumers, auto makers will certainly add it together with the infotainment. Question is what the feature is; HD front camera to capture incident in case of accident. ;)
Thanks, Bert. You raise some good points about "Ethernet switches" not being necessarily a good metric.
I think these two gentlemen who were asked questions happen to be in the business of developing automotive Ethernet switch chips -- thus they related their answers more to the potential market for their product.
Excellent article, Junko, which I think explains exactly how Ethernet is being and will be introduced into cars. Just as it has in may other control system environments, in spite of early stage frights by system designers.
I don't think the number of Ethernet switches in the car is a good metric for anything, though. A more important number would be the number of Ethernet hosts, i.e. end systems, connecting into the Ethernet network(s). An Ethernet "switch," which refers to a layer two "multiport bridge," is nothing more than a fan-out device in Ethernet nets. That's all. You do gain in survivability and reliability of you create a relatively dense mesh of switches, interconnected by multiple links, providing for redundant paths that can take over almost instantly if one breaks.
However there is not good correclation between the number of switches and the number of Ethernet end system, is my main point. I prefer many switches with not too many ports in each one. Others tend to go for fewer big switches.