Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

link failure and stopping the inline power supply

Hi,

CIPT document says that the inline power module of Cat6K(CatOS 5.5 or higher)/Cat4K (CatOS 6.1 or higher) automatically detects IP Phone by sending and receiving FLPs. Upon a receipt of FLP back from the IP Phone, the switch starts providing power. If the switch detects link integrity before the expiration of its 'wait-for-link' timer, it will maintain its power supply to the phone until it detects a link down event.

Now we have a question.

How about link down algorhtm/condition?

Does it, inline power port, follow the same convention as normal ethernet port? Does it declare a link failure after missing 3 keepalives? Then *HOW LONG* do we need to wait until the switch stops feeding the power to the port? This is an important question for us, service vendor. A user may connect his PC to the inline power port immediately after pulling off the IP Phone. If the switch does not stop its power supply within a short period of time, the user's PC is going to be affected. Please don't expect end users to follow a sort of "best practice". They will do whatever they want to do. And we need to have a precaution for such a case. Let us know the safety guideline.

thanks,

1 REPLY
Cisco Employee

Re: link failure and stopping the inline power supply

Here is a pretty good explaination of how the discover works for inline power.

http://www.cisco.com/warp/public/788/AVVID/ip_pwr_detect.html

Thank you,

-Mckee

87
Views
0
Helpful
1
Replies
CreatePlease login to create content