Unanswered Question
Jul 3rd, 2010
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Hi every one,

I have call manger 5 and alot of CISCO IP Phones. All phones work fine by Power over Ethernet PoE

Now, we have a office that is far from the main buliding about 185 m, I making LAN cable from Switch to Phone (about 190 m cable)

when tried to connect the CISCO IP Phone 7911, it gave "configuring IP" and after that gave "Disconnect ethernet"

Can any one tell me what is the problem ? and What is his suggestion to solve this ?

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Overall Rating: 5 (1 ratings)
William Bell Sat, 07/03/2010 - 06:18
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Based on the specifications for Ethernet/Fast Ethernet over twisted pair, the commonly accepted maximum distance between an Ethernet transmitter and receiver is 100 meters.  In my experience I have found that if you go much beyond that, you will have issues.  With Fast Ethernet I have seen distances beyond 100 meters but 190 meters would be well outside of what I have seen work.

In your case, you are almost twice that maximum distance.  You need to shorten that distance in some way.  If you are dropping a single phone then placing a local switch wouldn't make much sense.  There is a good thread on this exact topic here:

If you have multiple phones in the location, then you may want to run a single fiber pair and put in a local switch.



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