Introduction

In today’s fast-paced digital world, reliable mobile communication is crucial as well as enhancing mobile call quality. Mobile operators are constantly striving to provide their customers with seamless and high-quality call experiences. However, technical challenges such as silent calls, random echo, and short calls can significantly degrade the quality of service, leading to customer dissatisfaction. This case study explores how a leading mobile operator overcame these challenges by integrating Sevana PVQA Server into their existing call quality monitoring system.

The Challenge

The mobile operator in question was facing significant issues with call quality. Customers frequently reported experiencing silent calls, unexpected echo, and abrupt disconnections. Despite having an existing call quality monitoring system in place, the operator struggled to detect and diagnose these specific impairments. The limitations of their monitoring tools meant that many problematic calls went unnoticed, leaving the operator unable to address the root causes effectively.

Silent Calls

Silent calls occur when a call connects, but one or both parties cannot hear anything. This issue can be caused by network problems, faulty equipment, or software bugs. Silent calls not only frustrate customers but also increase the likelihood of them switching to a competitor.

Random Echo

Echo during a call can be highly disruptive. It typically results from network latency or misconfigured equipment. Echo can distort communication, making conversations difficult and leading to a poor user experience.

Short Calls

Short calls, where the connection drops unexpectedly after a brief period, are another significant issue. These interruptions can be caused by network instability, interference, or software errors. Frequent short calls can erode customer trust and loyalty.

The Solution: Sevana PVQA Server

To address these persistent issues, the mobile operator decided to implement Sevana PVQA Server as an additional module to their existing call quality monitoring system. Sevana PVQA Server is a sophisticated tool designed to analyze and monitor voice quality, providing detailed insights into various call impairments.

Implementation Process

The integration of Sevana PVQA Server was seamless and required minimal disruption to the operator’s existing infrastructure. The system began to work alongside the existing monitoring tools, augmenting their capabilities with advanced voice quality analysis.

Identifying Problems

Sevana PVQA Server quickly proved its value by identifying numerous instances of silent calls, echo, and short calls that had previously gone undetected. The system’s detailed analytics provided the operator with precise data on when and where these issues occurred, enabling them to pinpoint problematic areas within the network.

Root Cause Analysis

Armed with comprehensive data from Sevana PVQA Server, the operator conducted a thorough root cause analysis. They discovered that many silent calls were due to faulty network equipment, while echo issues often stemmed from improper configurations in their voice routing system. Short calls were primarily attributed to network instability in specific regions.

Resolving the Issues

With clear insights into the root causes, the operator took targeted actions to resolve the issues. They replaced malfunctioning equipment, reconfigured voice routing settings, and strengthened network stability in identified trouble spots. The proactive measures led to a significant reduction in call impairments.

Results and Benefits

The implementation of Sevana PVQA Server yielded impressive results. The mobile operator experienced a marked improvement in call quality, with a notable decrease in customer complaints regarding silent calls, echo, and short calls. Enhanced call quality monitoring allowed the operator to maintain higher service standards and improve customer satisfaction.

Increased Customer Satisfaction

With fewer call quality issues, customers enjoyed a more reliable and pleasant communication experience. This improvement in service quality helped in retaining existing customers and attracting new ones.

Operational Efficiency

By accurately identifying and addressing call impairments, the operator optimized their network operations. This efficiency not only reduced operational costs but also minimized the time and resources spent on troubleshooting.

Competitive Advantage

The proactive approach to call quality gave the mobile operator a competitive edge. Demonstrating a commitment to high-quality service reinforced their market position and brand reputation.

Conclusion

This case study highlights the critical role of advanced call quality monitoring tools like Sevana PVQA Server in enhancing mobile communication services. By effectively identifying, analyzing, and resolving call impairments, the mobile operator was able to significantly improve call quality and customer satisfaction. This successful implementation underscores the importance of investing in robust monitoring solutions to maintain high standards of service in the competitive telecom industry.

For more information about Sevana and our innovative products, Contact Us.

 

 

 

Voice quality issues can significantly impact communication experiences, whether you’re using traditional landlines, mobile devices, or Voice over IP (VoIP) systems. When users encounter problems like echonoiseclippingclicking, or dead air, it’s crucial to diagnose the root causes promptly. Let’s explore each issue and how to identify its source within the network.

  1. Echo:
  • Description: Echo occurs when you hear your own voice repeated with a slight delay during a call.
  • Causes:
    • Acoustic Echo: Sound from the speaker’s voice reflects back into the microphone due to room acoustics or speakerphone setups.
    • Network Echo: Delayed echoes caused by network latency or packet loss.
  • Diagnosis:
    • Listen for audible echoes during the call, or monitor your network with a tool that can detect and alert about echo in the payload, e.g. Sevana PVQA Server.
    • Test with different devices and environments.
  • Root Cause Analysis:
    • Check network latency and jitter.
    • Implement acoustic echo cancellation (AEC) algorithms.
  1. Noise:
  • Description: Background noise interferes with voice clarity.
  • Causes:
    • Environmental Noise: External sounds (e.g., traffic, wind) affect call quality.
    • Network Noise: Packet loss or glitches introduce artifacts.
  • Diagnosis:
    • Listen for unwanted sounds (buzzing, hissing, etc.) , or monitor your network with a tool that can detect and alert about echo in the payload, e.g. Sevana PVQA Server..
    • Test in different environments.
  • Root Cause Analysis:
    • Optimize network infrastructure.
    • Use noise reduction techniques.
  1. Clipping:
  • Description: Clipping occurs when an audio signal exceeds its maximum allowed limit.
  • Causes:
    • Amplifier Overdrive: Amplifiers push signals beyond capacity.
    • Digital Clipping: Signal exceeds the maximum level.
  • Diagnosis:
    • Listen for distorted audio during loud passages, or monitor your network with a tool that can detect and alert about echo in the payload, e.g. Sevana PVQA Server.
    • Check for square-wave-like waveforms.
  • Root Cause Analysis:
    • Avoid excessive amplification.
    • Ensure symmetrical output swing.
  1. Clicking:
  • Description: Clicks are sudden, brief disruptions in the audio.
  • Causes:
    • Network Glitches: Packet loss or interruptions.
    • Hardware Issues: Faulty cables or connectors.
  • Diagnosis:
    • Listen for intermittent disruptions, or monitor your network with a tool that can detect and alert about echo in the payload, e.g. Sevana PVQA Server..
    • Test with different devices.
  • Root Cause Analysis:
    • Monitor network stability.
    • Inspect hardware connections.
  1. Dead Air:
  • Description: Dead air refers to complete silence during a call.
  • Causes:
    • Network Drops: Temporary loss of connection.
    • Software Glitches: Call processing issues.
  • Diagnosis:
    • No audio for a period.
    • Abrupt silence during the call.
  • Root Cause Analysis:
    • Monitor network stability with a system that can detect and alert of audio gaps inside of the payload, e.g. with Sevana PVQA Server.
    • Update call processing software.

Conclusion:

Identifying the root causes of voice quality problems involves understanding the symptoms, analyzing the call payload, and addressing specific issues within the network. Proactive troubleshooting ensures better communication experiences. Upon all said above using automatic call quality monitoring system that can detect and alert on voice quality impairments inside the payload will significantly improve QoE and QoS problems root cause analysis. Remember that clear voice quality enhances productivity and user satisfaction! 🗣️🔊🚀

Introduction

In today’s interconnected world, reliable voice communication is essential for businesses, individuals, and service providers. Whether it’s a mobile call or a VoIP conversation, ensuring high-quality voice transmission is crucial. Enter Sevana QualTest, a cutting-edge solution designed to evaluate voice quality and network performance. In this article, we’ll explore the features, use cases, and metrics associated with QualTest.

Features of Sevana QualTest

  1. Mobile Test Probe: QualTest serves as a mobile test probe, compatible with Android-powered devices. It seamlessly integrates into both cellular and VoIP networks, allowing comprehensive testing.
  2. End-to-End and Single-Ended Testing: QualTest offers flexibility by supporting both end-to-end and single-ended call testing. Whether you need to assess the entire communication path or focus on specific segments, QualTest has you covered.
  3. User-Friendly Frontend: The intuitive frontend simplifies test setup. Users can specify calling and called parties, reference audio, and devices effortlessly. The frontend also provides real-time insights during testing.
  4. Detailed Reporting and Analysis: QualTest generates comprehensive reports, including overall quality Mean Opinion Score (MOS) over different time periods. It highlights successful and failed test calls, aiding troubleshooting efforts. Additionally, the system can analyze call audio contents using speech-to-text engines.
  5. Compatibility: QualTest works with both rooted and unrooted mobile phones. Analysis can be performed directly on the mobile device or on connected devices (e.g., Raspberry Pi for regular unrooted phones).

Use Cases

  1. Mobile Operators: QualTest empowers mobile operators to monitor call quality across their networks. By identifying bottlenecks and issues, operators can enhance user experience.
  2. Telecom Service Providers: Telecom providers leverage QualTest to assess voice quality in cellular and VoIP networks. It helps them optimize their services and maintain customer satisfaction.
  3. Telecom Solution Providers: Solution providers integrate QualTest into their offerings, ensuring robust voice quality testing for their clients.
  4. Test Engineers: QualTest is a valuable tool for test engineers involved in call quality assessment. It aids in diagnosing network-related problems and optimizing voice services.

Metrics and Analysis

  1. Network Metrics: QualTest measures critical network parameters, including Round-Trip Time (RTT), jitter, and packet loss for VoIP calls. These metrics directly impact call quality.
  2. Mean Opinion Score (MOS): QualTest calculates MOS scores, providing a quantitative measure of voice quality. Users can choose between reference audio or real call audio for MOS estimation.
  3. Waveform Analysis: By analyzing waveforms, QualTest correlates audio problems with network conditions. This helps pinpoint issues affecting voice quality.

Conclusion

Sevana QualTest is a game-changer in the field of voice quality assessment. Its versatility, detailed reporting, and compatibility make it indispensable for telecom professionals. Whether you’re an operator, service provider, or test engineer, QualTest ensures crystal-clear voice communication in an ever-evolving digital landscape.


Note: If you’d like to learn more about Sevana technologies or schedule a call with their development team, feel free to reach out!


Sevana: Contact Us: QualTest

Sevana AQuA: Promising Audio Quality Assessment for AMR-WB, EVS-WB, and EVS-SWB Codecs

Introduction

In the ever-evolving landscape of telecommunication technologies, efficient audio compression codecs play a pivotal role in delivering high-quality voice communication over limited bandwidth. The quality of audio codecs is traditionally assessed through Mean Opinion Score (MOS) testing, which involves subjective human evaluations. However, the need for automated, reliable, and consistent methods for evaluating codec quality led to the development of Sevana AQuA (Audio Quality Assessment) – a groundbreaking solution capable of differentiating quality based on MOS scores among various codecs, including Adaptive Multi-Rate Wideband (AMR-WB), Enhanced Voice Services Wideband (EVS-WB), and Enhanced Voice Services Super-Wideband (EVS-SWB).

The Significance of Codec Quality Assessment

As telecommunication providers strive to deliver crystal-clear voice quality over diverse networks, codec development has become a critical aspect of ensuring optimal user experience. The efficient utilization of bandwidth, reduction of latency, and preservation of voice naturalness are among the key parameters codec developers aim to enhance. Traditional subjective testing involves a panel of human listeners providing subjective quality scores, often measured by MOS. However, this process can be time-consuming, expensive, and potentially inconsistent due to variations in human perception.

Enter Sevana AQuA

Sevana AQuA represents a paradigm shift in codec quality assessment by leveraging advanced algorithms to automatically evaluate audio quality. The software analyzes audio samples encoded using different codecs, such as AMR-WB, EVS-WB, and EVS-SWB, and assigns them MOS scores based on a robust computational model. This model emulates human auditory perception, enabling AQuA to provide objective and repeatable quality assessments.

Key Features and Functionalities

  1. Objective Quality Scoring: Sevana AQuA employs advanced signal processing techniques and perceptual models to generate objective quality scores for each codec. These scores are highly correlated with human-perceived quality, making them an accurate representation of user experience.
  2. Codecs Comparison: The software enables direct comparisons of codec performance. Telecommunication companies and developers can assess how different codecs perform under varying network conditions, aiding them in selecting the most suitable codec for their requirements.
  3. Scalability and Efficiency: Sevana AQuA’s automated assessment eliminates the need for extensive human listener panels, reducing time and costs associated with quality testing.
  4. Wide Applicability: The software is versatile, accommodating different codecs and network conditions. It can be integrated into the codec development pipeline or used to assess codec performance in real-world scenarios.
  5. Continuous Improvement: Sevana AQuA can be fine-tuned and updated as new codecs are introduced or existing ones are optimized. This ensures that the evaluation remains up-to-date with technological advancements.

Conclusion

Sevana AQuA represents a pivotal advancement in the field of audio codec quality assessment. By offering automated, objective, and reliable MOS scoring for codecs such as AMR-WB, EVS-WB, and EVS-SWB, the software empowers telecommunication companies, developers, and researchers to make informed decisions about codec selection and optimization. As the demand for high-quality voice communication continues to grow, Sevana AQuA plays a crucial role in enhancing user experience across various networks and devices.

PCAP Analyzer - Passive Voice Quality Analysis
PCAP Analyzer – Passive Voice Quality Analysis

Sevana PCAP Analyzer: Pinpointing Audio Impairments and Unveiling Quality of Experience Issues Beyond Network Problems

Introduction:

In the realm of audio communications, ensuring high-quality sound and a seamless user experience is paramount. While network issues often contribute to audio impairments, they are not the sole culprits. Sevana PCAP Analyzer, an advanced tool designed for PCAP file analysis, goes beyond traditional network analysis by accurately pinpointing audio impairments and notifying users about potential quality of experience (QoE) issues, even when the network appears problem-free. This article delves into the capabilities of Sevana PCAP Analyzer and highlights how it revolutionizes the identification and resolution of audio-related problems.

  1. Unveiling Audio Impairments:

Sevana PCAP Analyzer employs sophisticated algorithms and signal processing techniques to detect and identify audio impairments within captured network traffic. By analyzing PCAP files, the tool can uncover a wide range of audio-related problems such as packet loss, jitter, latency, and echo, among others. These impairments can significantly degrade the quality of audio communications and adversely impact user experience. With Sevana PCAP Analyzer, network analysts gain a deeper understanding of the audio stream and can identify the root causes of impairments with precision.

  1. Pinpointing Non-Network Related Issues:

One of the unique strengths of Sevana PCAP Analyzer (unlikely Wireshark f.e.) lies in its ability to detect audio impairments and QoE issues that are not directly related to the network. Even in scenarios where network metrics indicate optimal performance, users may still experience poor audio quality. The tool analyzes audio signals within PCAP files to identify artifacts, distortions, and anomalies that might arise from codec issues, faulty hardware, software glitches, or other non-network factors. By accurately pinpointing these non-network related problems, Sevana PCAP Analyzer helps streamline troubleshooting efforts and ensures a superior audio experience for end-users.

  1. Real-Time Quality of Experience Monitoring:

Sevana PCAP Analyzer incorporates real-time monitoring capabilities to assess the quality of audio communications during live sessions. By capturing and analyzing network traffic in real-time, the tool provides immediate notifications and alerts about potential QoE and QoS issues. This proactive approach enables network administrators and support teams to intervene promptly, preventing a negative impact on user satisfaction. Sevana PCAP Analyzer offers a comprehensive set of metrics, including audio quality scores and MOS (Mean Opinion Score), to quantify the perceived quality and facilitate precise QoE monitoring.

  1. Detailed Analysis and Reporting:

Sevana PCAP Analyzer offers an array of analysis features that provide in-depth insights into audio impairments and QoE issues. The tool enables users to visualize audio metrics, and perform statistical analysis. Additionally, it generates comprehensive reports that capture the analysis results, facilitating documentation and sharing of findings with relevant stakeholders. These reports serve as valuable references for ongoing optimization efforts and troubleshooting collaborations.

  1. Integration and Collaboration:

Sevana PCAP Analyzer supports seamless integration with existing network analysis tools, audio processing systems, and communication platforms. This integration allows users to correlate audio impairments with network performance metrics, facilitating a holistic view of audio quality and enabling efficient troubleshooting. Moreover, the tool promotes collaboration among network analysts, audio engineers, and support teams by providing shared access to PCAP files, analysis results, and reports, thereby fostering a collaborative environment for problem resolution.

Conclusion:

Sevana PCAP Analyzer goes beyond traditional network analysis by accurately identifying audio impairments and shedding light on quality of experience issues, even when the network seems problem-free. With its ability to pinpoint non-network related problems, provide real-time monitoring, offer detailed analysis, and support integration and collaboration, Sevana PCAP Analyzer empowers organizations to deliver exceptional audio quality and ensure a superior user experience. By leveraging the capabilities

 

Messenger-to-messenger testing. How to test messenger-to-messenger voice and video calls?

This is how you can learn about your customers experience during the audio / video calls and find thin points and bottle necks in your service.

No call recordings, no privacy violation, but full details on the user quality of experience: low types of MOS scores (QoS and QoE), reasons for call quality degradation, pinpoints at the parts of the call audio where the quality had issues.

We promise easy and flexible integration into your messenger.

 

Do you have a hardware solution that records RTP call traffic in real-time? Enable QoE analysis to real-time RTP recording.

Are you happy with the E-Model quality scoring? Try out our user experience metrics. This will give you a competitive advantage and won’t take much effort for integration. Matching network conditions (E-Model, packet loss etc) with user experience (our analysis is based on actual call audio) will give you full picture on your network and user quality of experience (QoE).

Call center agents quality monitoring: do you have a call center that records customer calls and your agents complain about call quality?

Figuring out call quality issues, problematic routes might be much easier with Sevana PVQA technology.
Setting up massive call recording analysis is a matter of a couple of minutes. In return one receives audio quality score (MOS) and report on audio impairments that influenced the call quality.
By the end of the analysis, you will have full picture on the calls that had most of the problems in quality and potential reasons for them. Interested in receiving this information in real-time? This just simple with PVQA technology implemented for real-time traffic analysis. Contact us for more information.

How to setup real-time RTP monitoring?

One can easily setup real-time RTP monitoring using Sevana PVQA Server to receive information on calls with QoS (packet loss, jitter etc) and QoE (noise, dead air, echo etc) issues.

Unlikely other systems PVQA Server provides two quality metrics represented as two MOS scores: E-Model based MOS and PVQA MOS derived from call audio analysis.

With detailed statistics one can even figure out at what time of the call noise, echo, clipping or e.g. clicking took place.

Real-time alerting will immediately notify about quality issues of the monitored traffic. Book a demo here.