Telecom operator · anonymised case
Securing a telecom voucher management system
Designing a Voucher Management System connected to a telecom ecosystem, with unique generation, a reliable API and transaction logging.
Anonymous case. No screenshots. Confidentiality.
TelecomVMSAPITraceability
Context
A telecom operator needed to manage its technical ecosystem around SIM cards and top-ups. Scope included a Voucher Management System, a customer portal and a corporate website.
The VMS was the most sensitive part. It had to generate unique vouchers, expose them through an API and exchange data with a third-party telecom platform. Duplication, an untraceable transaction or downtime would have affected resellers and customers immediately.
Brand clarification
Legos was a platform integrated into the ecosystem. This describes technical compatibility and does not imply partnership or work performed directly for Legos. The operator remains confidential.
Main requirements
- guarantee voucher uniqueness;
- control the full lifecycle;
- authenticate and limit API calls;
- keep usable transaction traces;
- prevent retries from creating duplicate operations;
- monitor critical-component availability.
What we delivered
Lifecycle modelling
Voucher states and allowed transitions were defined before the API was exposed. A code could not be treated as both available and consumed.
API and idempotency
Critical operations supported controlled retries. A network failure would not turn a retry into a second transaction.
Exchange security
Technical access, secrets and permissions were separated by use. Logs identified the caller and processing performed without becoming a copy of sensitive data.
Operations
Monitoring covered errors, latency and processing queues. The operations team could distinguish a local incident from an external outage.
Customer portal
The portal supported SIM purchase and management, including top-up, tracking, useful codes and related information. A corporate website completed the public ecosystem.
Outcome
The operator gained a technical foundation for voucher generation, API exposure and SIM-related journeys. Traceability and operations were part of the product rather than additions after the first incident.
Transaction volumes, service levels and detailed architecture remain confidential.
Takeaway
Security in a transaction system is not limited to encryption. Uniqueness, idempotency, permissions and the ability to reconstruct an operation are controls too.
Our SRE and DevSecOps and right-cost development services can begin with an IT assessment.