Use Stun-Server
STUN is a protocol that allows suitable communication ports to be automatically negotiated for a smooth connection setup via NAT (Network Address Translation, RFC 3489) . This function is preset and does not usually need to be changed. Activate or deactivate STUN if required.
Use local SIP port (UDP)
By default, the phone dynamically handles all required communication ports with the SIP Server off. When the function is activated, the phone only uses the specified port for data exchange.
Use local RTP port (UDP)
As with the use of the SIP port, the phone dynamically negotiates all required communication ports with the SIP server. When the function is activated, the phone only uses the specified port for data exchange.
Quality of Service Rate
As of the Vista operating system and later, the telephone supports Quality of Service. Quality of Service is used to prioritize data packets. Each individual data packet is signed and given preference when forwarded to the switch or router. Please refer to the operating instructions. for information on whether your hardware supports Quality of Service