Duplex (auto ?!)

Unanswered Question
Sep 29th, 2008
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Hi There!

I'd like to know it is there any guideline about switch port configuration on duplex for IP Phones...

I received and information that switch ports for IP Phones should be configured as 100 full (of 1000 full) .. and not be set as auto...

Any help ?



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Chris Deren Mon, 09/29/2008 - 07:46
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It is the best practice to hard code 100Mb connections to 100/full, 1Gb connections on the other hand should be left at auto/auto. Keep in mind that some other phones i.e. 7906 are only 10Mb, so you dont want to hard code those. Since most customers have various phone types and they can easily be moved from port to port I typically leave the settings at auto/auto.



Rob Huffman Mon, 09/29/2008 - 08:00
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Hi Andrei,

Just to add a note to the great info from Chris. We have always followed the same rule of thumb (Auto/Auto)

Technical Tips

Network Interface Settings

In an IP telephony solution, Cisco recommends that the Ethernet interface for

Cisco IP Phones be set to Autodetection. Cisco recommends that other Ethernet

interfaces, including those for switches, routers, gateways, and Cisco Media

Convergence Servers (MCSs) be set to 100 Mbps/full duplex.

Page 492;


Hope this helps!



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