High quality VoIP technology

Using VoIP telephone application, there are many annoying troubles such as “spots spots sound breaks off in an important place”, “Can not hear a conversation” or “the partner is muffled and hears it”.

Based on longtime technical accumulation, Softfront wrestled for a study of “the media communication technology to realize rapid high-quality sound” to break off irritation of the VoIP, and the Softfront developed new VoIP communication method “REAFSVC“.

REAFSVC is the Softfront’s original new VoIP technology. The past VoIP technique is optimized for cabled networks, but our REAFSVC makes the quality of VoIP high on the mobile networks such as a cell-phone or the wireless LAN.

Very bad network with 10% of packet loss rates, REAFSVC achieves POLQA level more than 4.0 !

REAFSVC always watches states of the networks and transmits and receives media data and always adjusts the parameter that is most suitable for the network such as cell phone network or wireless LAN network. The sound quality improvement is larger than other VoIP product.


Figure. The results of POLQA values evaluated

What is POLQA ?

POLQA (Perceptual Objective Listening Quality Analysis)  is a internatinal standard of methods to evaluate the quality of the sound and can evaluate objectively that of the HD sound. The sound quality indicates in 1(Bad) to 5(Good).

Three characteristics of REAFSVC

(1)  Not to break off in a bad network.

In conventional VoIP technology, it uses with parameters decided at the beginning of the call (packet size and transmission interval).


Figure. Parameters of conventional VoIP

It makes the sound cut off many times.


Figure.  Sound breaking off in conventional VoIP technology

REAFSVC always analyzes the state of the network and dynamically optimizes the parameters in real time according to that situation, preventing unpleasant sound breaks.


Fiture. REAFSVC controls VoIP packets

(2) Clear voice like CD

The clarity of the voice is determined by the “resolution” of the sound called “sampling rate”. The larger the sampling rate, the larger the amount of data = packet size.
For this reason, with the conventional VoIP technology, the sampling rate is reduced to reduce the packet size so as to reduce the influence of the network condition.
With REAFSVC, with a sampling rate of 48 kHz, high sound quality above CD is realized.

Sampling Rate Quality
8,000Hz Analog PSTN phone, IP Phone
16,000Hz VoLTE
32,000Hz FM Radio
44,100Hz CD
48,000Hz REAFSVC

(3) REAFSVC supports various systems such as smatphones, server systems

REAFSVC technology is implemented on our product  “SUPREE embedded AudioEngine“. Of course, it is compatible with conventional VoIP technology, and it is also possible to talk with existing VoIP products. It supports not only to one-to-one calls, but also to one-to-many conference configurations.


Figure. REAFSVC  system  example