Subnet   Start IP   End IP
  185.19.236.0/22     185.19.236.0         185.19.239.255  
   
  Service     Port number
  SIP   5060 UDP  
  5060 TCP  
  5061 TLS 
  RTP     ANY PORT - UDP 
  Provisioning

  https://dm.yealink.com
  https://api-dm.yealink.com
  https://rps.yealink.com

  51.11.241.228
  20.19.96.56
  20.242.144.0
  20.242.144.1
  52.71.103.102
  35.156.148.166
  106.15.89.161
  47.75.58.202
  47.89.187.0

  80 TCP  
  80 TLS  
  443 TCP  
  443 TLS
  443 UDP 

  Fonzie C2D + SIP calling

  49.13.57.124
  116.203.244.240
  WebRTC 8088-8089/TCP
  RTP 10000-60000/UDP
  websockets.myfonzer.com of 116.203.115.89 poort 4343
  88.198.109.252 poort 1323 (Yealink telefoonboek)


Niet vergeten: SIP Application Layer Gateway (SIP ALG) uitschakelen.