Question : IP Telephone

I was told that there is a fire hazard in connecting an IP Telephone to a ethernet switch with power supplied by the switch. Can anyone verify this or lead me to an article stating this.

Answer : IP Telephone

zzdanny,

Hi Danny,

Apologies for taking time to pick-up on your question.  I am a IP Telephony specialist and will be happy to answer your questions.

Firstly, there is no fire risk from using line-powered IP phones.  I am fully aware of the Cisco range only, but the same solution will apply.

Certainly you should by 1 system (e.g. all Cisco, or all 3Scum {sorry, I meant 3Com}) as there will be compatibility issues.

Cisco make line-powered switches but currently only the 3548 and 6500 range support this.  They use a proprietary method to determine whether there is an IP phone on the end of the cable - thus, stopping 48V being supplied to a PC NIC.  Currently, these have to Cisco Phones only (although the method has been standard- submitted).

So to answer your question - yet it does work, no there is no fire risk, but you have to keep to one vendor currently.

If you have any other questions whatsoever please don't hesitate to contact me - oh and I no longer work for the Collective (Cisco), but am an independent voice consultant - so I'll be happy to tell you the real truth.

Many thanks,
Stuart
[email protected]k