When you plug in a SIP phone, it contacts its defined configuration server (either Polycom or Yealink). The manufacturer site in turn redirects the phone to provisioning and media servers on the globalmeet.com domain where it is managed.
Allow communications to the following domains and ports listed below. Pin-holes must be preserved on a per-session basis for the outbound ports on globalmeet.com.
|Domain||Inbound Ports||Outbound Ports||Purpose|
|*.globalmeet.com, *.*.globalmeet.com||25 TCP||Optional. For fax-to-email service.|
|80, 443 TCP|
|5060, 7000 TCP/UDP||SIP call setup and handling|
|5061, 7001 TCP||SIP call setup and handling|
|16384-32768 UDP||RTP/ RTCP multimedia streaming for call audio|
|*.pool.ntp.org||123 UDP||Time syncing on connected SIP phones and other devices|
|*.polycom.com||80, 443 TCP||Polycom conference and desk phones|
|*.yealink||80, 443 TCP||Yealink conference and desk phones|