Voice Fraud Protection
Real-time detection and blocking of IRSF, Wangiri, traffic pumping and PBX hacking across every trunk and route - with velocity controls, destination policy, revenue assurance and analysts who act on the alerts.
< 60 s
Detection-to-block
3B+
Minutes screened per year
24×7
Fraud desk
What is Voice Fraud Protection?
Voice Fraud Protection is the control layer that inspects every call attempt across Dollu's voice platform for the patterns that turn into unpayable invoices: international revenue-share fraud to premium destinations, Wangiri one-ring callbacks, traffic pumping to inflated-rate numbers, compromised PBXs dialling overnight, SIM-box bypass and subscription fraud on new accounts. It runs in the signalling path, so a decision to throttle or block is applied to the next attempt, not to next month's bill.
The engine combines rules you control with models we maintain. Velocity limits by CLI, trunk, destination and account; spend caps by hour, day and month; allow and block lists at country, operator and prefix level; and time-of-day policies form the deterministic layer. On top, behavioural analytics score each account against its own baseline and against network-wide intelligence - hot-listed number ranges, destinations under active IRSF attack, ASR and ACD signatures of pumping - so a compromised trunk is caught even when each individual call looks ordinary.
For carriers and wholesale customers, protection extends to revenue assurance: reconciliation of routed minutes against supplier invoices, detection of margin leakage from mis-rated destinations, and identification of downstream customers whose traffic profile has changed in ways that suggest fraud on their own networks. For enterprises on SIP trunks, the same engine watches for PBX and voicemail compromise, out-of-hours dialling and unusual destination mixes, and applies caps that keep any breach financially bounded.
Behind the tooling is a 24×7 fraud desk in the NOC. Analysts review high-severity alerts, contact you before blocking legitimate but unusual traffic where the policy allows, work with upstream and downstream operators to shut down active schemes, and issue post-incident reports. Fraud rules and hot-lists are also exposed by API so you can integrate them into your own switch or SIEM.
Why choose Dollu for voice fraud.
The advantages of buying from a carrier that owns its network, interconnects and operations - rather than a reseller.
Losses bounded before they happen
Spend caps and velocity limits enforced in real time cap the worst case for any trunk or account, so a breach costs hundreds rather than tens of thousands.
Detection that adapts
Behavioural baselines and network-wide hot-lists catch new schemes and low-and-slow attacks that static rules alone would miss.
Fewer false positives
Per-account baselines, analyst review on high-severity alerts and configurable notify-before-block policies keep legitimate campaign traffic flowing.
Protection for your margin, not just your bill
Revenue assurance reconciles minutes and rates so mis-billing, leakage and downstream fraud show up in the portal instead of at year end.
People on the other end of the alert
A 24×7 fraud desk investigates, liaises with other operators and reports back, so your team is not alone with a dashboard at 03:00.
Compliance support
Controls and evidence trails that support regulatory expectations on fraud and nuisance calls, including STIR/SHAKEN attestation handling on US traffic.
Capabilities in detail.
Everything included with Voice Fraud Protection - the platform features, options and controls you get from day one.
- 01
Real-time fraud scoring
Every call attempt scored in the signalling path against rules and behavioural models; actions include allow, alert, throttle, challenge and block, applied to the next attempt.
- 02
IRSF and premium-destination defence
Continuously updated hot-lists of number ranges and destinations under IRSF attack; per-destination velocity and spend limits; automatic blocking of unallocated and premium ranges.
- 03
Wangiri and callback abuse
Detection of one-ring campaigns on inbound numbers, callback-rate anomalies to premium ranges and CLI ranges associated with Wangiri, with automatic inbound blocking and subscriber protection.
- 04
Traffic pumping and pumping-friendly routes
ASR, ACD and destination-concentration signatures of artificially inflated traffic; supplier route checks for pumping susceptibility; alerts on rate-deck anomalies.
- 05
PBX and account compromise
Baseline models per trunk and account; alerts on out-of-hours dialling, new-destination bursts, concurrent-call spikes and credential-guessing patterns; auto-throttle within policy.
- 06
Velocity, spend and destination policy
Limits by CLI, trunk, sub-account and destination; hourly, daily and monthly caps; allow and block lists at country, operator and prefix level; time-of-day and day-of-week rules.
- 07
Revenue assurance
Reconciliation of routed minutes against supplier CDRs and invoices, mis-rating and margin-leak detection per destination, and downstream customer profile-change alerts.
- 08
Fraud desk and case management
24×7 analyst review of high-severity alerts, notify-before-block workflows, operator liaison to shut down active schemes and post-incident reports with recommendations.
- 09
API and integration
REST API and webhooks for alerts, rules, hot-lists and case status; export to SIEM and BI tools; optional real-time feed of blocked ranges for your own switch.
How it works.
From first conversation to live traffic - a tracked, engineer-led onboarding with a named owner at every step.
- Step 01
Profile
We analyse your historic traffic to build per-trunk and per-account baselines and identify existing exposure such as open premium destinations or unbounded trunks.
- Step 02
Set policy
Agree velocity limits, spend caps, destination lists and the notify-versus-block posture per trunk or customer segment. Rules go live in the portal.
- Step 03
Protect
Scoring runs on every call. Alerts, throttles and blocks apply automatically within policy; the fraud desk reviews high-severity cases and contacts you as agreed.
- Step 04
Review
Monthly reports cover blocked traffic, prevented spend, false-positive rate and revenue-assurance findings, and policies are tuned with your team.
Premium, Standard or Wholesale.
Every destination on the Dollu rate deck is offered in up to three quality tiers. Pick per destination - or per customer - and mix them on one interconnect.
| Dimension | Premium (CLI-guaranteed) | Standard | Wholesale |
|---|---|---|---|
| CLI delivery | Guaranteed - the originating number is delivered intact to the called party | Best effort - CLI is normally delivered but not contractually guaranteed | Not guaranteed - CLI may be withheld or replaced on some routes |
| Route type | Direct operator interconnects and Tier-1 partners only | Direct and vetted partner routes, quality-steered in real time | Least-cost blended routes, swapped freely to hold the price |
| Typical ASR band | Highest | High | Variable |
| PDD | Lowest | Low | Variable - can rise on multi-hop transit |
| Best for | Contact centres, retail and enterprise traffic, OTP voice calls - anywhere the called party must see who is calling | Business traffic where quality matters and CLI is helpful but not mandatory | High-volume carrier, dialler and call-centre traffic where price per minute dominates |
| SLA | Per-destination ASR, ACD and PDD targets with service credits | Quality targets monitored and reported; credits on core availability | Core availability only; route quality is managed, not guaranteed |
| Price position | Highest | Mid | Lowest |
All three tiers ride the same SIP interconnect, portal and CDRs - the tier is chosen per destination prefix, so you can move traffic between them without a new set-up.
Who uses this and why.
Typical deployments across carriers, enterprises, platforms and contact centres.
Wholesale carriers and aggregators
Protect margin against IRSF and pumping on both sides of the switch, and spot downstream customers whose traffic suggests they have been compromised.
Enterprises with SIP trunks
Cap the financial impact of PBX or voicemail compromise with spend limits, destination policy and out-of-hours rules on every trunk.
UCaaS and CPaaS platforms
Per-tenant fraud policy and subscription-fraud detection so a stolen card or a compromised tenant does not become your carrier bill.
MVNOs and calling brands
Subscriber-level velocity limits, SIM-box detection and Wangiri protection for retail international calling and callback services.
Contact centres
Guard outbound campaigns from mis-dialled premium ranges and inbound numbers from callback abuse, without blocking legitimate high-volume dialling.
Technical & commercial specifications.
Key parameters at a glance. Ask us for the full service description and SLA document.
| Fraud types | IRSF, Wangiri, traffic pumping, PBX/voicemail hacking, SIM-box, subscription fraud |
|---|---|
| Detection | Real-time scoring in signalling path; rules plus behavioural models |
| Response | Allow, alert, throttle, challenge, block; typically under 60 seconds |
| Controls | Velocity by CLI/trunk/account/destination; hourly, daily, monthly caps |
| Policy | Country, operator and prefix allow/block lists; time-of-day rules; hot-lists |
| Revenue assurance | Minutes and rate reconciliation; margin-leak and mis-rating detection |
| Fraud desk | 24×7 analysts; notify-before-block; operator liaison; incident reports |
| Integration | REST API, webhooks, SIEM export, blocked-range feed |
| Reporting | Monthly prevented-spend, blocked-traffic and false-positive reports |
| Availability | Included with Dollu voice services; standalone for own-switch operators |
How Voice & Wholesale is priced.
Wholesale voice is priced from an A–Z rate deck: a rate per destination and breakout for each quality tier, billed on connected seconds. There are no setup or port fees on SIP interconnects.
We publish the model, not a public rate card - actual rates depend on destination, route class, volume and regulatory cost. See how every Dollu service is priced.
- A–Z rate deck in USD, EUR, GBP or INR
- Premium (CLI), Standard and Wholesale tiers per destination
- 1/1 billing on most destinations; 60/60 flagged on the deck
- Volume tiers from 1M minutes a month; bilateral and swap for carriers
- Rate increases with at least 7 days’ notice; decreases immediate
- Billing
- Prepaid (online top-up, auto-recharge) or postpaid net-15/30 after credit review; per-second increments
- Commitment
- None - month-to-month usage; optional volume commitments unlock better tiers
230+ destinations, A–Z.
Every country on the rate deck, in Premium, Standard and Wholesale tiers where the market supports them - over 600 direct carrier interconnects and Tier-1 partners. Country guides cover the destinations with the most traffic.
Voice Fraud - your questions answered.
The questions customers and carriers ask us most often before they interconnect. If yours is not here, our team answers within one business day.
Still have a question?
Ask our solutions teamRelated services.
Services customers commonly combine with Voice Fraud Protection.
Find out what your trunks are exposed to.
Share 30 days of CDRs under NDA and our fraud desk will return an exposure assessment and recommended policy within five business days.
