Understanding ASR and CSSR: Key Performance Indicators in Telecom

Introduction to ASR and CSSR

In the telecommunications industry, the quality and reliability of a network are paramount. Two critical Key Performance Indicators (KPIs) that help measure these aspects are ASR (Answer Seizure Ratio) and CSSR (Call Setup Success Rate). These metrics provide insight into the effectiveness and efficiency of telecommunication networks, guiding operators in maintaining and improving service quality.

What is ASR?

ASR (Answer Seizure Ratio) is a measure of the number of successfully answered calls out of the total attempted calls in a network. It is expressed as a percentage and is calculated using the formula:

[ \text{ASR} = \left( \frac{\text{Number of Successfully Answered Calls}}{\text{Total Call Attempts}} \right) \times 100 ]

A high ASR indicates that a majority of call attempts are successfully connected and answered, reflecting good network performance. Conversely, a low ASR suggests issues such as network congestion, routing problems, or other technical difficulties that prevent calls from being completed successfully.

What is CSSR?

CSSR (Call Setup Success Rate) measures the percentage of calls successfully set up compared to the total call attempts. It focuses on the initial connection phase of a call rather than its completion. The formula for CSSR is:

[ \text{CSSR} = \left( \frac{\text{Number of Successfully Set Up Calls}}{\text{Total Call Attempts}} \right) \times 100 ]

A high CSSR indicates that the network can establish connections reliably, which is crucial for maintaining user satisfaction and trust in the network’s reliability.

Importance of ASR and CSSR in Telecom

Enhancing Customer Experience

High ASR and CSSR values are directly linked to customer satisfaction. Users expect their calls to connect quickly and reliably. Frequent call drops or failures can lead to frustration and dissatisfaction, prompting customers to switch to competitors with better network performance. Thus, maintaining high ASR and CSSR is crucial for retaining customers and building loyalty.

Network Performance Monitoring

ASR and CSSR are vital for monitoring and diagnosing network performance. They provide insights into potential issues within the network infrastructure, such as hardware failures, software glitches, or routing problems. By regularly monitoring these KPIs, operators can identify and address issues promptly, ensuring optimal network performance.

Regulatory Compliance

In many regions, telecommunications regulators mandate specific performance standards for network operators. Maintaining high ASR and CSSR values helps ensure compliance with these regulations, avoiding potential fines and penalties. It also demonstrates a commitment to providing high-quality services, enhancing the operator’s reputation.

How to Measure ASR and CSSR

Data Collection

Measuring ASR and CSSR involves collecting data on call attempts and their outcomes. This data is typically gathered through network monitoring systems and call detail records (CDRs). These systems track various metrics, including call initiation, connection, and completion statuses.

Calculation

Once the data is collected, calculating ASR and CSSR is straightforward. For ASR, divide the number of successfully answered calls by the total call attempts and multiply by 100 to get a percentage. For CSSR, divide the number of successfully set up calls by the total call attempts and multiply by 100.

Tools and Software

Various tools and software are available to automate the measurement and analysis of ASR and CSSR. These tools provide real-time monitoring and reporting, enabling operators to quickly identify and address performance issues. Some popular tools include:

NetScout: Offers comprehensive network performance monitoring and analysis.
SolarWinds: Provides robust network management solutions with detailed KPI tracking.
Nokia Siemens Networks NetAct: A management system for monitoring and optimizing network performance.

Factors Affecting ASR and CSSR

Network Congestion

High levels of network traffic can lead to congestion, resulting in failed call attempts and lower ASR and CSSR values. Congestion can occur due to inadequate infrastructure, high user density, or unexpected spikes in usage. Managing network capacity and load balancing are essential to mitigate congestion and maintain high KPI values.

Routing Issues

Incorrect or inefficient routing of calls can negatively impact ASR and CSSR. Routing issues can arise from outdated routing tables, misconfigurations, or software bugs. Regular updates and audits of routing protocols are necessary to ensure optimal call handling.

Hardware and Software Failures

Failures in network hardware, such as switches, routers, or transmission equipment, can disrupt call connectivity. Similarly, software glitches or bugs can impede call processing. Regular maintenance, timely upgrades, and proactive monitoring are crucial to prevent and address such failures.

External Interference

External factors such as weather conditions, physical obstructions, or electromagnetic interference can affect signal quality and lead to call failures. While some of these factors are beyond control, optimizing network infrastructure and using advanced technologies can mitigate their impact.

Best Practices for Improving ASR and CSSR

Capacity Planning

Effective capacity planning involves anticipating and managing network load to prevent congestion. This includes upgrading infrastructure, adding more transmission lines, and optimizing resource allocation. Proactive capacity planning ensures that the network can handle peak loads without compromising performance.

Regular Network Audits

Conducting regular network audits helps identify and rectify potential issues before they escalate. Audits involve checking hardware, software, routing protocols, and overall network performance. Implementing recommended changes from audits can significantly improve ASR and CSSR.

Advanced Routing Techniques

Using advanced routing techniques, such as dynamic routing and load balancing, can enhance call setup success and answer rates. These techniques optimize the routing paths based on real-time conditions, ensuring efficient call handling and reducing the likelihood of failures.

Implementing Redundancy

Redundancy in network infrastructure ensures that there are backup systems in place to take over in case of hardware or software failures. This includes redundant servers, switches, and transmission lines. Implementing redundancy minimizes downtime and maintains high ASR and CSSR values.

Monitoring and Analytics

Continuous monitoring and analytics provide real-time insights into network performance. Using sophisticated monitoring tools, operators can track KPIs, identify trends, and detect anomalies. This allows for prompt intervention and continuous optimization of network performance.

Conclusion

ASR and CSSR are critical KPIs in the telecommunications industry, reflecting the quality and reliability of network services. High values for these metrics are essential for customer satisfaction, regulatory compliance, and overall network performance. By understanding the factors affecting ASR and CSSR and implementing best practices, telecom operators can enhance their network’s performance, ensuring a high-quality user experience.

References

By focusing on these critical aspects and implementing recommended strategies, telecom operators can ensure their networks deliver reliable and high-quality services, maintaining high ASR and CSSR values.