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Community Member

VoIP and half-duplex

Hello all,

I have a VoIP solution from Inter-Tel. I can't seem to get the phones out of half-duplex. It is a dedicated T1, with a 1720 on one side and a 26xx on the other side. Is there a special config I need to use or is this an Inter-Tel issue. I noticed that on the fasteternet interface it is set at half-duplex. Could this be the problem?

Thanks in advance for the help

Community Member

Re: VoIP and half-duplex

If you change the port configuration setting value for the SW port, you must change the PC port to match. Also, this setting should match the setting on the switch's port to which the phone is connected.

Follow these procedures to set the speed of the switch port on the Cisco IP Phone.

Cisco IP Phone 7960/7940


Step 1 Press the Settings button.

Step 2 Use the Navigation button to select Network Configuration, and then press the Select softkey.

Step 3 Scroll to SW Port Configuration.

Step 4 Press the Edit softkey.

Step 5 Use the buttons on the dial pad to enter the selected option.

To enter letters, use the numbers associated with a particular letter. For example, the 2 key has the letters ABC. For a lower case "a," press 2 once. Press the 2 key repeatedly to scroll through the available letters and numbers. Pause after the selected letter appears on the screen.

Valid values are as follows:

A (auto negotiate)

10H (10BaseT/half duplex)

10F (10BaseT/full duplex)

100H (100BaseT/half duplex)

100F (100BaseT/full duplex)

Use the << softkey to correct any mistakes.

Step 6 Press the Validat softkey.

Step 7 Press the Save softkey to save this change.

Hope this helps,


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