It was way back in 1989 that I had finished with the fun of living at a University College and moved into a flat with some friends. The first analogue cellular mobile phone call was made in Australia on 23 February 1987 so very few people actually had a mobile – and certainly not millennials struggling to pay the rent in Newtown. The four of us living in a flat had an old-fashioned landline (only one outlet) and when we made phone calls, we wrote down in a little book beside the phone where the call was made and for how long. At the end of the month, we would tally up all the calls and it would inevitably fall short of the total non-itemised bill. It was clumsy and time-consuming – but we knew no better.

It was only several years later when itemised billing was introduced and this was seen as a huge step forward. Bills started coming out with every call made and the cost of every call. Now that would have made life easier. I have never been able to find out if it was just an urban myth or real but apparently divorce rates spiked at this time as partners started questioning certain numbers called when they saw them on the bill – and they were found to be calls made to people who were more than just ‘friends’. Apart from this minor inconvenience for people who were caught with their pants down (literally) the introduction of itemised bills was a technological leap forward.

The next step along similar lines was the introduction of Calling Number Display (CND) in December 1997. This gave us the ability to see who was calling before we even answered the phone. As much as that gave us call screening abilities, it also allowed us to see who had called us when we couldn’t take the call and then call the person back. That sounds like a great idea and, used effectively, makes our lives more convenient.

Unfortunately, there are always people out there with sinister motives. The latest technological scam that has hit our shores takes advantage of our reliance on CND. The scam works like this. First, you need to setup a premium service that charges people a per second rate when they call the number. There are a number of legitimate operators of premium numbers and in Australia they typically start with 1900 (they used to be 0055 numbers but changed to 1900 with our 10-digit numbering scheme). One of my old companies ran a 1900 service for tech support and you will often see 1900 numbers used for competition lines or adult chat lines. In Australia the services give an announcement when you call them so you know that you are being charged for the service but in other countries they don’t have the same restriction. So in undertaking your first step, make sure the premium number you setup doesn’t have a pesky announcement telling people they are going to be charged. Second step is to then make sure you can make a call that either legitimately sends that premium number to another handset or spoofs that premium number. That way when you ring someone, it appears to be from that number. The third step in this simple scam is to setup an automated (or manual) process to call as many mobiles as possible for one second. The cost to call someone without the call being answered is zero so the ongoing cost in this scam is nothing. Then you sit back and count the (illegitimately gained) money as it rolls in! You are relying on the modern technology we have as well as the famous human curiosity that killed the cat. When most people see a missed call from an unknown number, they wonder who it was from. There is no message left so they start to wonder who called them. Eventually, it becomes too much and they return the call. The scammer at this point has the call answered and the person is told to wait on and they will get someone and they either leave the phone with nothing or put it on hold and let you listen to music – which is costing you several dollars a minute to hear! The entire purpose at this stage is to keep you on the phone as long as possible.

The message here is simple. When you see that missed call, before you call back have a good look at that number. If you don’t recognise the format, maybe don’t call the number back.

Mathew Dickerson

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