Re: [802.3_RTPGE] PoE Ad-hoc questions - final

["Hugh Barrass (hbarrass)" <hbarrass@xxxxxxxxx>]

Geoff,

 

That’s an interesting thought. If that line of thinking is used, then the requirement would be that the PHY specification is “compatible with PoAE” – in other words, that the PHY is able to be implemented in such a manner that does not interfere with the delivery of power. For example, if the PHY uses a band-limited definition and leaves the DC-xxxKHz band free, then a splitter can be used to insert power in the same manner as POTS or DSL.

 

Of course, there’s a whole spectrum between “use PoE” and “let the implementer design it.” We could also consider different levels of specification.

 

Hugh.

 

 

From: Geoff Thompson [mailto:thompson@xxxxxxxx]
Sent: Tuesday, June 12, 2012 5:21 PM
To: STDS-802-3-RTPGE@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_RTPGE] PoE Ad-hoc questions - final

 

Dave-

I think there is a larger question to be answered here.
That would be:

Does the automotive industry actually want "standardized PoE" of the same style that the current PoE standard provides?

That is, does the auto industry really want the sort of multi-vendor plug-and-play facility that we provide along with its lack of optimization for cost?

The alternative would be for them to do PoAE (Power over Automotive Ethernet) on a more finely tuned basis.  That is, each instance (with specific exceptions*) would be "engineered" to closely match supply size, conductor size, fault detection and PD characteristics to each specific application within the vehicle.

In such a context a standard might not be necessary or the PoAE standard might be much more wide open than the current standard with the expectation that each connection and the component connection options on each end would be designed by engineering experts.  Sort of (conceptually) more like Ethernet over fiber than Ethernet over twisted-pair.

* The specific exceptions being user accessible accessory interfaces which would use the existing standard.

Best regards,
    Geoff

Geoffrey O. Thompson
GraCaSI S.A.
Mountain View, CA 94043
<thompson@xxxxxxxx>

On 126//12 3:15 PM, Dave Dwelley wrote:

All -

 

Here is the final question list from the PoE Ad-hoc in Minneapolis. End users (automotive/industrial/other): please look at this list and be prepared to discuss these points in San Diego.

 

Thanks to those who contributed questions, and I look forward to seeing you at the Plenary -

 

Dave