Tigo employs risky strategies to fight simboxing

Tigo Ghana has said they would not recommend their anti-simboxing strategies to any telco because though it is efficient, it is also tedious and risky.

The daily detection records would show that Simboxing on the Tigo network keeps reducing faster than on any other network, arguably because the telco is continuously making its network on attractive to fraudsters.

But Chief Technical Officer of Tigo Ghana, Obafemi Banigbe told Adom News in an exclusive interview that the result Tigo is getting, comes at a very high cost and through a risky strategy, which can be avoided through regulation.

He said apart from the fact that the strategy pose a risk to Tigo, it is basically a detective strategy and not necessarily a preventive one since it only notices SIMBOX numbers after they have been used for a while.

Banigbe explained that Tigo has employed the services of two vendors outside of Ghana to be making 1000s of calls to the Tigo network on daily basis, and the vendors have servers installed on the Tigo network in Ghana.

He said because the vendors know the numbers they call and the numbers they use in making the calls, when the call terminates on Tigo through a different number, they put those detected terminating numbers into the server sitting in Ghana and the Tigo system picks them up every 15 minutes and blocks them.

"We have algorithms that determine particular numbers being used in a pattern over a period of time and we use that to determine which numbers need to be blocked. Those numbers are put in what we call A Number Blocking List, which is a list of Tigo numbers blacklisted from originating calls on our network," he said.

The Tigo CTO however added that once the SIMBOX operator detects that they are not able to originate calls with those Tigo numbers, they just remove them from the simbox and buy new SIM cards.

He said the down side is that some numbers get to be used for fraud over a longer period before they are finally blocked because there is need to determine there is a pattern relating to those numbers.

"But you can be sure that once we confirm a Tigo number in a simboxing activity on our network it will be blocked in 15 minutes and we report the numbers which are not Tigo numbers to the respective operators who have two hours by law to block the. Within those two hours the number continues to be used for simboxing," he said.

The risk

Banigbe said tampering with the A Number Table every 15 minutes is where the risk was, because it means other alterations could be made to the records without being detected since automatic back up occurs only at 12 midnight everyday.

"Initially when we started this rigorous process we tampered with the list and therefore detected SIMBOX numbers once every 24 hours then we came to once every two hours and then to once every one hour but now we are doing once every 15 minutes, which the designers of the switches would not recommend," he said.

Banigbe explained that the system only backs itself up automatically at 12 midnight every day, so if there was corruption in the system and the system breaks down the latest back up the company could depend on would be the back up from 12 midnight.

According to him, that would mean every change made between 12 midnight and the time of the breakdown would be lost, so records of any other tampering with the system would also be lost and so any possible corruption in the system would be hard to detect.

The Tigo CTO said even though their strategy is risky, "we felt the need to make a statement to fraudsters that our network cannot be used for simboxing but we would not recommend same strategy to other telcos."

“We are committed to saving the state money being lost to simboxing but we are doing so at our own risk,” he said.

Regulation He how we believes the single move that can prevent and not just detect simboxing is the removal of the 19 cents floor price for a minute of incoming international traffic.

Banigbe thinks even if telcos and the state corrected all the flaws in the national identification verification and sim registration systems, that would still not be enough to prevent simboxing once the financial motivation still exist.