Quality of Service (QOS)
DiffServ
Requirements:
Existing and enabled DiffServ support on all active network components
DiffServ is used to prioritise the handling of language packages (VoIP) and to achieve better voice quality for VoIP calls. DiffServ can be evaluated in networks that include active network components such as routers or switches, to enable packets to be forwarded according to their priority.
As proposed in RFC 4594, the DSCP values are set for VoIP calls (signalling (SIP): CS5, voice (RTP): EF).
*Note: DiffServ is usually not supported by VoIP providers. As a result, this setting may not be taken into consideration under certain circumstances on the Internet.
*Note: To adopt the change, reboot the PBX.
*Further help under VoIP