Yes you can use the Polycom IP 5000,6000, or 7000 depending on the size of your conference room. Go to this link: https://www.adtran.com/web/url/phones and then click on "Polycom IP Phones" and then you will them at the bottom of the list. The 7100 is pre-configured to support those models and they will appear as a supported phone from the drop down list when you go to add it.
Let me know if you have any further questions.
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