This list is a modified version of the list provided within the natvpn project licensed GPLv2 with edits made per comments on github. Please note these are servers operated and maintained by 3rd parties and are not within control of the FreePBX project.
stun.l.google.com:19302
stun1.l.google.com:19302
stun2.l.google.com:19302
stun3.l.google.com:19302
stun4.l.google.com:19302
stun01.sipphone.com
stun.ekiga.net
stun.fwdnet.net
stun.ideasip.com
stun.iptel.org
stun.rixtelecom.se
stun.schlund.de
stunserver.org - stunserver Resources and Information.
stun.softjoys.com
voiparound.com
stun.voipbuster.com
stun.voipstunt.com
stun.voxgratia.org
stun.xten.com
turn.respoke.io:443