I believe the standard should approach this, but state that one cannot
put 2P to one PD and another 2P to a second PD. This starts to make
things much more complex. If anything, have a PD that splits the power
to the two devices individually. We need to set some limits in our
efforts or this can go on for years as others will start to find mini
loop-holes to work with.
Derek
Geoff Thompson wrote:
Yair-
My opinion is that the question below needs to be a formal decision of
the group in session. We should put the question on the agenda of
"issues" for July.
Geoff
At 12:40 AM 6/8/2005 , Yair Darshan wrote:
Hi
Geoff
Thanks for the reply.
Yes, I understand that it is no law issue. When I use "legal" I
meant conformance to the relevant standards.
According to your last conclusion, I understand that splitting 4 pair
cable to 2 outlets (each outlet gets 2 pairs) is valid scenario which
PoEp has to address too.
Now we will have the following PD options:
High Power 4P PD
Or two High Power 2P PD's
Or two IEEE802.3af PDs
Do we really want detect and power all options or we wish to detect and
power only 4P or 2P high power or single IEEE802.3af PD and only
prevent
damage to two IEEE802.3af PDs connected to the same cable and leave the
decision if to power it or not to the system (implementation specific
etc?).
Yair
From: Geoff Thompson
[mailto:gthompso@xxxxxxxxxx]
Sent: Tuesday, June 07, 2005 6:56 AM
To: Yair Darshan
Cc: Geoff Thompson; STDS-802-3-POEP@xxxxxxxxxxxxxxxxx
Subject: RE: [8023-POEP] 2P v 4P and safety [Unscannable
attachment] [Unscannable attachment]
Yair-
"legal" vs. common...
There is no matter of law involved, only conformance with voluntary
standards.
If you insert a splitter into a single outlet then there is no
conformance issue.
If you split a cable to 2 outlets you are not conformant with TIA-568.
The US has always "required" that you run a single 4-pair cable
to each RJ-45.
The International Standard, ISO/IEC 11801 does not require this. It was
an international fight of long standing. The German national body and a
major international connector manufacturer (US headquartered) bitterly
opposed mandating 4 pair per outlet. Therefore, 2 pair is allowed.
I hope this helps.
Geoff
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