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Which is more commonly supported for power delivery (switches) and endpoint kit (access points, cameras)? From reading around it would appear that Mode A is the more flexible and so should be more prevalent, but I need a sanity check.
This post brought to you by "that POE switch is disturbingly cheap, I wonder what's wrong with it".
From what I understand Mode A should be more prevalent - certainly anything supporting gigabit speeds and PoE seems to use Mode A (Power over Ethernet - Wikipedia, the free encyclopedia)
The PSE, not the powered device (PD), decides whether power mode A or B shall be used. PDs that implement only Mode A or Mode B are disallowed by the standard. in theory then your device supplying the power should be capable of both ways.
Ben
Anything that is gigabit and requires poe has to use mode a as there are no spare pairs for mode b operation.Quote:
Originally Posted by Soulfish
Ben
Beware of classes too, there are some issues with how switches negotiate power with devices. For example, one 24 port switch may have a total of 140 watts power to give to devices. If your devices are class 0 (don't negotiate and usually use draw the full 15.4 watts regardless of what they actually need) or class 3 (high power, always draw 15.4 watts) then you'll run out of POE by port 10...
Other switches, usually the more expensive ones, have a full 15.4 watts available on each individual port, so you'll have no issues expanding later! Might be cheaper using a separate injector and swtich. PowerDsine stuff is nice and reliable.
Cheers, that's what I hoped. Spotted a ~£200 Not-Linksys-any-more-it's-a-Cisco-really-guv 8-port Gigabit POE switch (SRW2008MP-EU) that can deliver 15.4w port for an outbuilding and was wondering what was wrong with it.