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Testing...hello??? Helloooooo???




Hi Dan,
yes the reflector is working.

I wanted to add a few things to you list.

1) goal: achieve the lowest possible cost at the DTE load end:
   a) possibly allow for non-isolated DC/DC converter (in those cases where safety rules allow this)
   b) simplest lowest cost identity network at the DTE load end

2) Discover on the same wires as power, yes, but beyond that, we should check to see that all 4 of those wires are going where they are supposed to go; no opens, crosses, or shorts. Most discovery techniques do not fully address this issue.

3) all proposed implementations must account for the cable discharge effect that can occur when the data cable is plugged in. The cable discharge effect should not cause any damage to functionality of discovery, power delivery, or safety.

4) In the case of DC power, do we need auto polarity, like MDI/MDIX, or polarity independent power, or a discovery method that determines when the correct polarity (as well as wiring) is present?

5) common mode termination on all lines, I believe that we need this to maintain signal margins.

6) Isolation at the MDI power source port. We know that we need isolation on each RJ45 port to frame ground. Do we need isolation from one port to another, whether the power on that port is on or off, and if so how much isolation?
I think that we need isolation, for if nothing else, fault isolation in the case where a powered device decides to blow, and somehow sends power back down the line. This power should stop at the switch port.


I hope that you are not sorry you asked whether the reflector was working.

thanks,
- Rick Brooks




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>From: "DOVE,DANIEL J (HP-Roseville,ex1)" <dan_dove@hp.com>
>To: 'DTE Power' <stds-802-3-pwrviamdi@ieee.org>
>Subject: Testing...hello??? Helloooooo???
>Date: Wed, 15 Mar 2000 09:43:30 -0700
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>
>Is this reflector working?
>
>>  Hi All,
>>  
>>  On my plane ride home, I took some time to type up a list of things
>>  that need to be done on this project. It may not be the 
>>  ultimate list, 
>>  but I thought I would share it with the group to get the 
>>  ball rolling.
>>  If I forgot to put something down, feel free to add to the list, or 
>>  better yet, volunteer to perform some of the items listed.
>>  
>>  Regards,
>>  
>>  Dan Dove
>>  ___________     
>>  _________________________________________________________
>>  _________    _/    ___________  Daniel Dove         
>>  Principal Engineer __
>>  _______     _/        ________  dan_dove@hp.com     LAN PHY 
>>  Technology __
>>  _____      _/           ______  Hewlett-Packard Company      
>>            __
>>  ____      _/_/_/ _/_/_/  _____  Workgroup Networks Division  
>>            __
>>  ____     _/  _/ _/  _/   _____  8000 Foothills Blvd. MS 5555 
>>            __
>>  _____   _/  _/ _/_/_/   ______  Roseville, CA 95747-5555     
>>            __
>>  ______        _/      ________  Phone: 916 785 4187          
>>            __
>>  _______      _/      _________  Fax  : 916 785 1815          
>>            __
>>  __________  _/ 
>>  _________________________________________________________
>>          I n v e n t !
>>  
>>  DTE ISSUES MATRIX
>>  
>>  --------------------------------------------
>>  AC or DC Power?
>>  --------------
>>  - AC Frequency, voltage, other issues?
>>  - DC Switcher impulses, filtering, other issues?
>>  
>>  Detection Method?
>>  ----------------
>>  - FatLinkPulses
>>  - Diode Detection (Current Sense)
>>  - Diode Detection (Voltage Sense)
>>  - Constant Current Sink
>>  - Other?
>>  
>>  Which pairs?
>>  ------------
>>  - 12,36 impact on 10/100
>>    - DM/CM conversion characteristics vs frequency
>>    - 100BASE-T noise immunity
>>    - Switcher frequency content
>>  - 45,78 impact on installed base coverage
>>    - CM/CM coupling between pairs
>>  EMI
>>  ---
>>  Common-mode insertion
>>  - Conducted EMI
>>  - Radiated EMI
>>  - Susceptibility 
>>  
>>  MidSpan Insertion
>>  -----------------
>>  - Transformer coupling
>>  - Return Loss w/wo power
>>  - Insertion Loss
>>  - EMI 
>>  - Susceptibility
>>  - Detection method compatibility
>>  
>>  Safety
>>  ------
>>  - SELV limits
>>  - Japanese or other International limits
>>  
>