Telecom Fraud Checklist: CLI, Wangiri & Simbox

Fraudulent activity in voice, SMS, billing, and routing can severely impact telecom operators leading to revenue loss, degraded quality of service, and even customer churn. Early detection of warning signs is crucial. Use this checklist to verify whether your systems and processes capture potential fraud indicators.

Check “Yes” if the condition is met, and leave it unchecked if not.

CLI Refiling Fraud

CLI Refiling fraud occurs when fraudsters manipulate Caller Line Identification (CLI) data to disguise the origin of a call. This misdirection can lead to misrouted calls, revenue leakage, and network abuse.

Checklist for CLI Refiling fraud

• [ ] Customer Complaints: Are there reports of unusual call behavior or unauthorized charges related to caller ID discrepancies?
• [ ] Abnormal Traffic Patterns: Do you notice unexpected spikes or dips in call volumes or anomalies in call-routing data?
• [ ] Data Mismatch: Are there discrepancies between caller IDs recorded in different network nodes (e.g., MSC vs. IN)?
• [ ] Revenue Discrepancies: Do your records show a significant difference between projected revenue based on expected CLI routes and the actual revenue collected?
• [ ] Quality of Service Anomalies: Have you detected issues such as call drops or unusual delays that correlate with potential CLI manipulation?

Wangiri Fraud

Wangiri fraud involves a tactic where fraudsters trigger missed calls to bait recipients into calling back premium-rate numbers, resulting in unexpected charges. This activity can inflate call volumes and distort usage metrics.

Checklist for Wangiri Fraud

• [ ] Customer Complaints: Do customers report unexpected charges or unusual call-back patterns linked to missed calls from unfamiliar numbers?
• [ ] Traffic Anomalies: Are there sudden increases in missed call volumes, particularly from international or high-cost originators?
• [ ] Destination Spikes: Do you observe a concentrated spike in calls directed at specific premium-rate numbers?
• [ ] Billing Mismatches: Do your billing records reveal discrepancies between expected call volumes and revenue figures that correlate with Wangiri fraud scenarios?
• [ ] Quality Degradation: Is there degraded service quality or call consistency during periods of suspected fraudulent activity?

Simbox Fraud (On-Net & Off-Net)

Simbox fraud involves the use of devices (SIM boxes) to reroute international calls through local SIM cards. This can occur in both off-net and on-net environments, resulting in reduced tariffs and significant revenue loss.

Checklist for Simbox Fraud

• [ ] Customer Complaints: Are there frequent complaints about unexpected charges, call quality issues, or network congestion that might be linked to SIM box activity?
• [ ] Traffic Pattern Anomalies: Do you detect unusual call volumes or call patterns, such as multiple calls in rapid succession or calls originating from unusual geographic areas?
• [ ] Data Source Mismatches: Do call records from different network nodes (e.g., MSC, IN, billing systems) display discrepancies that suggest unauthorized routing?
• [ ] Revenue Forecast Differences: Do your projections for international call revenue differ significantly from actual revenue, indicating potential SIM box bypass?
• [ ] Technical Quality Metrics: Are there noticeable drops in call quality KPIs like latency, jitter, or throughput during periods of suspected SIM box activity?

Conclusion

Maintaining a robust fraud prevention system is essential for telecom operators to secure revenue streams and ensure superior Quality of Service. This checklist provides a structured approach to identifying indicators of CLI, Wangiri, and Simbox fraud. Regularly reviewing these aspects will help you pinpoint vulnerabilities early and take corrective action.

By integrating this checklist into your daily monitoring and reporting routines, you can not only protect your revenue but also enhance customer satisfaction and trust. For more advanced prevention and monitoring tools, consider exploring data-driven solutions like Synaptique’s offerings.