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Great Voice-over-IP (VoIP) speech quality 

Not only is minimal latency absolutely essential for Voice-over-IP, it is the single most important factor in improving speech quality. 

Traffic Shaping technology does keep ping times low and transfer rates consistently high at the same time. RTP detection integrated in cFos and cFosSpeed permits prioritizing VoIP and other live streams (like conference channels). Its prioritization can be adjusted under Protocol or Program Settings. Should a particular live stream not be recognized, you can prioritize the respective program by name.

Please note that some programs (like VoIPBuster) only use RTP but not the corresponding RTCP connection. For these, you should deactivate strict RTP verification in the settings.

Dropouts During Download:

VoIP connections usually suffer from dropouts when downloads are simultaneously run at full speed. Thanks to their integrated RX shaping, cFos and cFosSpeed help avoid this problem by keeping ping times consistently low.

Skype:

Skype employs a proprietary encrypted protocol that cannot be detected by a Layer-7 analysis without considerable effort. To allow users to prioritize Skype nevertheless, we have entered it in our program list. 

VoIP via Router Prioritization:

Some routers (like the Fritz!Box) ship with phone jacks installed on the device. If a jack is used, all VoIP data will be transmitted directly to the Internet passing cFos and cFosSpeed by entirely. The major drawback here is that to avoid dropout, such routers restrict the available bandwidth drastically whenever a VoIP call is made or accepted. This may have a negative impact on Traffic Shaping performance, since this also means the connection is repeatedly subject to strong variations in speed. This is why we recommend you make all VoIP calls from your computer itself to allow cFos and/or cFosSpeed to detect and prioritize them.

Optimizing Connection Settings:

You can specify exactly what transfer medium you use under Connection Settings. The more information about a connection is available to cFos or cFosSpeed, the better ping times will be. Default is "Adaptive." But if you were for instance using a DSL connection, you should select the appropriate DSL standard or protocol as your medium.

Favor Ping:

In addition, you can also use the settings in the context menu or status window to activate "Favor Ping." A green arrow will then show up on the status window. This setting will have cFos or cFosSpeed do everything to keep ping times to a minimum but at the expense of transfer speed, which may slow down considerably.