Polycom – Microsoft CX Handsets Setup Notes

The Polycom CX IP handsets gets all its info (NTP server parameters, where to downloading root CA certificate, what is OCS IP address, … ) via the DHCP configuration.

By experience, all the issues I have seen with that phone were related to mis-configuration in DHCP

The pre-requisites for the phones to work would be:


  • OCS installed and configured
  • DHCP configured for : IP, Mask, Gateway, DNS
  • DNS configured with 2 SRV location records:
    • One SRV record for OCS server IP discovery
    • One SRV record for NTP server IP discovery
  • Root CA certificate should be in Active Directory
  • Auto-Enrollment should be configured in the Domain Controller for automatic Root CA certificate download


Thanks to Brahim Ait Oumeri – one of Polycom’s UCC Solutions Architects for providing the information.


A useful tool to check you DHCP/DNS setup can be found here – http://www.insideocs.com/Tools/MOCLogin.htm



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