Real-time network statistics and KPIs one can benefit from using PVQA Server

Learn about network MOS and variety of waveform KPIs related to impairments that affect voice quality in real-time
📞 Agility
Add proactive maintenance layer based on PVQA call quality monitoring and let your support engineers be notified when call quality issues prevail in conversation
⠀📞 Quality issue root-cause discovery
Based on impairments analysis speed up problem root-cause identification, discover packet loss patterns inside the call audio
⠀📞 Flexible setup
Integrate PVQA library into existing system or create a new one suitable for any hardware and OS
Keep an eye on call quality with Sevana!

How to find call issues that affect callers’ perception?

Sevana PVQA analysis detects and informs about such annoying problems inside the call audio as:

VAD clipping – this impairment detects incorrect work of Voice Activity Detector (VAD). Detector finds edges of active and inactive fragments of the signal considering VAD worked too late (in the beginning of the speech) or too early (in the end of the speech).

Clicking – is a single energy spike in the spectrum of the audio, which may happen for different reasons.
Audio gaps – is a zero-signal level inside speech, a gap in speech that may be caused by different reasons.
Dead air – is a constant signal level inside speech and may have positive and negative value.
Noise – this means that noise level present in the call affects human perception and disturbs the caller.

… and will also let you discover patterns of impairments specific to certain suppliers, partners, or other networks:

Click + DeadAir-01 – high probability that packet loss affected the call audio
Click + VAD clipping – possible packet loss

Caller quality of experience measurement. Do you know about issues bothering your callers that you might not know?

Sevana PVQA technology detects these impairments to predict caller’s quality of experience aside from network quality of service:

💡 Silent Call – one leg of the voice call has no speech (silentcall)

💡 Echo – this is typically due to a blockage or mismatch, which results in the signals bouncing back from where they came. Additionally, the presence of echo effect in packet switched networks can be traced back to the functionality of the line. Where standard lines function with a delay of 10 milliseconds, packet switched networks can have up to 400 milliseconds of delay. As a result, the echo effect is much more noticeable.

💡 Amplitude clipping – is typically a result of a misconfigured voice gateway on the voice path.

💡 Dynamic clipping – notifies about possible clipping happening in another network as the audio waveform corresponds amplitude clipping, however, it is not present at the moment.

These and other impairment detectors allow you an effective caller quality of experience measurement. Contact us to learn more.

How to make mobile test call from one mobile phone to another?
Using Sevana QualTest it is easy:

✅Measures quality of mobile calls with regular non-rooted Android phones and iPhones
✅Enables uploads and shares test results
✅Runs both active (with reference audio) and passive tests
✅May be integrated with QualTest Host and correspondent Backend to automate making and receiving mobile test calls
✅Measures quality of mobile calls in the field
Within QualTest one can easily setup these two test scenarios:
🔊 initiate test calls and measure MOS when installed as system application. It is available on rooted phones only. One can view / share / upload test results right from the phone.
🔊 initiate and accept calls without analysis on mobile phone. Rooted phone is NOT required. In this mode application notifies its desktop (Raspberry Pi) counterpart (Qualtest Host, further down QH) about progress of the call. QH handles audio streams via cable adapter and communicates with backend.

How to quickly setup SIP / VoIP call quality testing?

Using QualTest it’s easy:
🔘 Quick way to measure quality of SIP / VoIP call without installing complex software solutions
🔘 Runs on Linux (including ARM builds)/ macOS/ Windows operating systems:
🔘 Quality measurement is based on Sevana waveform analysis technology and network statistics such as packet loss, jitter etc (E-Model)
Keep an eye on call quality with sevana.biz

 

What are Sevana call quality testing offerings?
We are happy to offer all kinds of tools to test call quality in any network: VoIP, GSM, 5G, satellite
🔹 Vast call quality monitoring both on audio and protocol levels
🔹 Passive real-time and active scheduled call quality analysis
🔹 Call quality problem root cause analysis
🔹 Reliable network and payload MOS
🔹 Mobile-to-mobile call quality tests

contact center end-to-end voice quality testing
Contact Center end-to-end voice quality testing value clients and agents

Forecasting voice quality using network statistics was sufficient for the days when one could control the network.

Different suppliers, networks, systems, software, hardware influence customer and agent experience. Only network metrics cannot ensure that all entities involved in the voice path work properly and give the best or satisfactory quality of caller experience (QoE).

Using network parameters to calculate MOS for cloud-based contact center and agent connection does not represent possible issues inside the cloud or voice paths connected to it.

Automation of test calls simulating caller and agent activity that will play audio file of “excellent” quality (the so-called reference audio) over the environment and record actual audio received by correspondent endpoints will give objective quality score for the whole voice path if one can compare the reference and test files for quality loss.

Sevana AQuA makes this comparison fast and easy providing reliable MOS score and reports on various quality issues that affected the caller perception. Furthermore, AQuA will pinpoint timestamps of the conversation where the problems occurred and indicate the type of impairment, which will help to identify the “faulty” part of the voice path.

This approach is useful at any stage of deployment – evaluation, piloting, transition, or production. If on demand, or scheduled voice quality scoring is not enough one can use Sevana PVQA for real-time voice quality analysis, problems alerting and reporting within the same feature of indicating impairments that affected the quality loss, but in real time.

Waveform analysis is the approach that gives objective overview on voice quality in cloud contact centers. Sevana tools perform perfectly well for voice quality measurement and analysis in the cloud.

Sevana AQuA is the most flexible too for end-to-end voice quality testing:
🖋 Testing across multiple devices and networks
Improve your system’s QoE and invest in the future – waveform analysis works seamlessly for VoLTE, VoWiFi, RCS or any other approach
🖋 Flexible integration considering every client’s requirement
Feel free to develop your own call quality monitoring solutions implemented by your own staff
🖋 Easy integration into any kind of hardware
Work on any hardware of your choice
🖋 Automated and fast testing cycle reducing operating costs
Save time and money using automated quality monitoring system
🖋 Streamline root cause analysis
Automate call quality assessment and ease problem root cause identification
🖋 Customer-oriented support
We are always happy to help save our customer’s time
Keep an eye on call quality with sevana.biz

Do you want to know about call quality issues prior your customers start complaining?

Sevana libraries collect all the QoS and QoE data of the calls in real-time, providing immediate alerting on changes that affect callers’ perception, discover and store reasons for call audio degradation.

Map audio impairments on network metrics and discover QoE and QoS patterns, specific to certain routes, destinations, originations, or parts of the traffic. Every call, analyzed by the system, creates big data that one can study, using data analysis tools, to predict network behavior and call quality.


Sevana PVQA – Passive Voice Quality Analyzer is the tool that will help you with this task.
It is a unique powerful tool to non-intrusively (without comparing with reference audio file) evaluate voice quality by waveform analysis. PVQA MOS is perhaps the most accurate compared to other tools that predict MOS score by single file waveform analysis. Tool performance and ability to work in real-time give companies an opportunity to develop their own voice quality testing solutions not being dependent on particular hardware and software. PVQA is available as a cross platform application or library for all main desktop and mobile operating systems. Keep an eye on call quality with sevana.biz