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3com 4500g with 7912g Cisco IP phones 1

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joeazer

IS-IT--Management
Jan 15, 2007
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hi,
i've been having a problem with the 7912g cisco phoes where they cannot draw power from my srw224p Linksys switch.

as far as i've known , those phones do not support the 802.3af standard and are supposed to be running with cisco "inline power" POE standard.

in my case i cannot change the phones so i'm looking for a compatible Switch to carry those phones.

one of the switches available for me is the 3com 4500g 48 or 24 port switch.

can anyone help me with confirming if this switch can carry the mentioned Cisco phones?

if not , what are my options regarding switches.

thanks in advance :)
 
No. You need a Cisco PoE switch or a Cisco PoE compliant power injector (or power shelf). Either that or power the phones with individual PSU's.
You will loose out on automatic Voice VLAN's by NOT using a Cisco switch which should be a concern........

HTH

Andy
 
That says a lot for "industry standard" doesn't it????
 
The problem is Cisco Pre-Standard PoE ISN'T an industry standard. IEEE 802.3af is the standard and all new Cisco IP Phones support this (7970, 7971, 7941, 7961 etc), as you have seen the older Cisco IP Phones only support Cisco Pre-Standard PoE and therefore require a Cisco PoE switch (or pawer shelf).

Andy
 
As far as I can tell the "End-of-Life" announcement for the 7912g phone was issued Sept 2006. If fact you can still order one until March 2007. The standards for POE were approved June 2003.

So they are in effect selling POE hardware that is NOT standards based even TODAY!

It is quite a stretch to ignore Cisco's constant and blatant proprietary systems. I find it amazing that they continue to hold so much market share in spite of these "owner hostile" practices. Go figure :)
 
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