What tends to make CDR processing “reliable at scale”
If picking one feature that usually moves the needle most, it’s end-to-end reconciliation (your “missing records” point) backed by sequence checking. In practice, duplicates are painful, but missing or late CDRs are what create revenue leakage, customer disputes, and month-end panic. A solid control total approach (counts, sums of durations/bytes/charges, per switch/MSC/SGSN and per time window) gives a clear “received vs expected vs rated vs billed” view, and it’s auditable.
Queue management is the next big one for scale, but it only helps if it’s paired with idempotency. When retries happen (and they will),downstream consumers must be able to safely reprocess the same record/file without double-rating. That usually means stable unique keys, dedupe windows, and “exactly-once” behaviour achieved through design rather than wishful thinking.
Validation is often underestimated: schema checks, header/trailer totals, file hashes, and strict parsing rules stop bad data contaminating everything downstream. The trick is to validate early but quarantine rather than block the whole pipeline—treat it like a production line with a reject lane.
For error handling, the most reliable setups separate “poison” records, keep a full replay log, and alert on SLA breaches (age of oldest message, backlog size, missing sequence ranges),not just on exceptions.
If this were being run inside a UK Ltd (or for a carrier supplier contract),these controls also make life easier for billing disputes, SOC/ISO audits, and proving completeness to finance without heroic manual work.