[Tfug] Yet another poser

[Rich]

On Sep 14, 2007, at 6:48 pm, Rich wrote:

> I found a site a while ago where a sysadmin listed  the contents of
> his (custom-built) cable kit. It was something like this:

Actually, more like this:
http://www.ossmann.com/5-in-1.html


On Sep 17, 2007, at 7:08 pm, johngalt1 wrote:
> Unless someone can explain a real world application of a
> crossover cable using POE, I call BS. This sounds way too
> hypothetical.

PoE devices still require PoE whatever device they're connected to.  
If you connect a PoE device to a PC, you need a crossover cable *and*  
it should carry power. Real world application? Simple:

	big wide world <-> PC <-> wireless base station

The base station runs off power over ethernet, the PC supplies it,  
but you have to use a crossover cable.

Some more points to consider:
  - PoE is only usually carried over 4, 5, 7 & 8. Other times it's DC  
on 1, 2, 3 & 6. See figures 1 and 2 in the following piece:
    [http://www.bb-elec.com/tech_articles/Power_Over_Ethernet.asp]

  - Many chipsets can re-cross a crossover cable automagically. My  
PowerBook, for example, can be connected to a standard network with a  
crossover cable. Similarly, I can connect this to another computer  
(Mac or otherwise) with a straight through cable. I suspect some PoE  
devices might work this way too, so although it's *wrong* and a quick  
hack to use a crossover cable for infrastructure, if it *can* be  
supported, then the cable should be wired appropriately.

Thankfully, I don't get my ethernet cables from John Galt Enterprises  
Inc.! :-P

R.