title	Roaming Billing CDR Validation Lab
emoji	📡
colorFrom	blue
colorTo	indigo
sdk	docker
app_port	8501
pinned	false

Roaming Billing CDR Validation Lab

A self-directed telecom integration project that validates simplified TAP-style roaming CDR records, detects billing and settlement issues, and generates reconciliation/test reports.

This project does not implement the proprietary GSMA TAP3 ASN.1 file format. It uses mock CSV records to demonstrate roaming billing validation logic, partner reconciliation, issue reporting, and launch-readiness thinking.

Why this project exists

The Technical Roaming Integrations Engineer role requires understanding of roaming integrations, billing systems, Wireshark/networking tools, operator onboarding, test reports, and issue resolution. This lab focuses on the billing-validation and integration-documentation part of that workflow.

What the project validates

• Mandatory field completeness
• Duplicate CDR detection
• IMSI format validation
• Known VPMN partner validation
• Currency validation
• Event timestamp consistency
• Service/tariff matching
• Charge rating mismatch detection
• Sequence-number consistency
• Partner reconciliation summary
• Markdown test report generation

Project structure

roaming_billing_cdr_validation_lab/
├── data/
│   └── mock_roaming_cdrs.csv
├── reports/
│   ├── validation_issues.csv
│   ├── reconciliation_summary.csv
│   └── validation_test_report.md
├── src/
│   ├── validator.py
│   ├── reconcile.py
│   └── generate_report.py
├── tests/
├── run_project.py
├── requirements.txt
└── README.md

How to run

python run_project.py

Expected output:

Validated 12 records.
Found validation issues.
Reconciliation summary written to reports/reconciliation_summary.csv
Markdown test report written to reports/validation_test_report.md

Example CV bullet

Built an independent roaming billing validation lab using Python to process mock CDR/TAP-style usage records, detect missing fields, duplicate records, rating mismatches, invalid partner identifiers, currency errors, and settlement anomalies, and generate reconciliation and test reports for HPMN/VPMN-style workflows.

Interview explanation

This project demonstrates how I would approach roaming billing integration validation before commercial launch. I created mock usage records, defined mandatory fields and partner/tariff rules, detected blocking issues, summarized settlement totals by HPMN/VPMN/service type, and generated a test report suitable for technical handover.