Bad Stuff End User nuisance calls and messages

Nuisance Ministers on Nuisance Calls

Forgive me but I don’t hold the Department of Culture, Media and Sport (DCMS) in very high regard when it comes to technology issues. It’s a very personal thing, dating back to the Digital Economy Act, their blinkered approach and refusal to listen to anyone who wasn’t an ageing rock star (or paid by an ageing rock star).

Culture Secretary Maria Miller trumpeted something over the weekend that, according to the substantial press coverage at least, should reduce the current high volume of unwanted marketing and other nuisance calls.

I’m confident the plans announced will do very little to reduce the deluge I currently get.

Why? Because spammers have shown themselves time and time again to give not a toss about rules and regulations.

For example, I signed up to the Telephone Preference Service (TPS) years ago, and have recently re-added my numbers just in case. Little help it does.

To understand why one has to look at the economics.  TPS is a for-profit money making service run by the Direct Marketing Association (DMA).

The DMA charge to query its database – around £2,200 per annum, plus VAT. So from the start there is a disincentive for Joe Bloggs Marketing Co Ltd to use it. Better subcontract the calling overseas, with a paper requirement to check TPS and full deniability if their agents get busted calling my housebound, blind and painfully immobile 98-year-old grandmother an hour after she goes to bed of an evening.

The Solution

Is painfully simple. Put a legal requirement on on Telephone Service Providers (TSPs) via the forthcoming legislative overhaul of the Communications Bill to provide, free of charge, effective call blocking tools.

You see, TSPs like BT, Virgin Media, Sky and the rest actually make money from nuisance calls through so-called termination charges. They get paid for putting the nuisance call through to you, so there is little real incentive for anyone in the industry to tackle the problem.

Subscribers like you and I can pay, around £5 per month (£60 per year) for the privilege of having nuisance calls blocked at the exchange – but I see that as blackmail; I pay enough already to rent a phone line. My service provider is making money from the misery of a nation by accepting termination charges from marketeers who hound me 12 hours a day.

Now, if every telephone service provider was obliged through their operator’s license to provide a free and effective nuisance call blocking service then it would be a different story.

Exchange-level blocking is far more powerful than the little black boxes one can buy to filter calls before they hit your handset.

For example, if the call originates in the UK, even if the caller withholds their number, the exchange still knows the ID of the originating caller.

BT therefore, if you pay them for the privilege, provide a blocking service that allows users to dial a special code immediately after a “number withheld” call to block further calls from that number, without affecting calls from your local doctor’s surgery, who happens to withhold their number when calling me.

By the way, what I said above about spammers ignoring rules and regulations, a rule prevents a marketing company calling you withholding their number. Yet this goes on day in, day out.

So a legal obligation on all telephone service providers to provide free blocking tools like the one I described from BT. We’ll all use it if it’s free, and marketeers will have to find a new way to inflict their pain.

After all the current Government, as per the DCMS, is a big fan of free blocking (switched on by default) when it comes to web pornography and the like.

But Miller and Co at the DCMS are probably too busy slapping themselves on the back for the positive press over the weekend to listen to my advice. After all, a DCMS minister openly ignored my advice after inviting me to give it face to face.

James Firth

By James Firth

Tech blogger previously at ComputerWorldUK and Slightly Right of Centre. CTO of Comprobo, a British technology start-up.

20 replies on “Nuisance Ministers on Nuisance Calls”

spot on James!
Having broken free from BT and now on a community run fibre network I have migrated to a voip service from vonage, and can use my mobile on it, and I have found my mobile (iphone) can block callers who have called me, so why can’t that happen with all phones? There must be a simple way to do it as you say.
keep the faith, the dinosaurs who rule us will soon be superseded by men of fibre and vision.

Good post James. Interestingly amongst the most read posts on this blog are the ones quoting telephone numbers of legitimate UK based telemarketing organisations who must clearly be thought of as pests by the general public or they wouldn’t be googling the phone number.

Particularly active numbers are 08000641087
and 01616626518

“Interestingly amongst the most read posts on this blog are the ones quoting telephone numbers of legitimate UK based telemarketing organisations…”

You can see why the numerous “who called me?” sites have sprung up with people interested in tracing dodgy calls. Unfortunately many of these sites have become super spammy themselves!

Action by the likes of the NHS and corporates to present a meaningful CLID is also required, I routinely tell them that if they call and withhold I won’t answer it and if they won’t leave a message they are not going to be able to communicate with me by phone.

Perhaps blocking all withheld numbers is better, that would make them change their ways. Per-call release of CLID is standard for those who genuinely need to keep their number to themselves.

Chris – you may block callers who have called you, but it’s the new ones that are the problem. If they use a range of numbers to send from even more tricky. Is Vonage blocking based on the full network CLI or just the presented one?

Good to see the clearing time changed to stop scams.

No reason why all companies should not send a meaningful CLI. And people who do not send a CLI can use 1470 to send it on particular calls.

The CLI number should also give the name of the company by law if it goes to a message.

The current peak termination rate at the BT exchange is 0.0137 pence per minute. There are 24ish million households in the UK, of which no more than 16% are mobile only.

That’s 84% with a landline or a round 20m. Let’s say each of those receives 3 calls a day and are answered for 20 seconds a piece. No answer incidentally means no termination revenue but a cost of powering the line to make it ring. That’s 20x3x20 million / 60 mins of revenue a day – £2,470 a day – actually spread out amongst a competitive industry involving some 250 operators.

I would suggest that the “moral hazard” of the termination revenues on fixed lines at least is immaterial and inconsequential; especially considering that it costs c50 pence per minute to run their contact centres which receive numerous complaints on the issue. The same analysis using the mobile termination rate yields a much higher result of course, but my experience is that landlines are targeted especially.

There’s also an inherent assumption that the network CLI hasn’t been modified. Alas, the organisations making these calls have as much regard for international standards as they do for TPS in many cases.; all they need is a session border controller and an interconnected network somewhere in the world that looks the other way .

Keeping aside the fact that BT’s exchanges can’t do this (being museum pieces) User-invoked (has to be his way – blanket blocking at a network level is contrary to EU law) blocking, white lists, black lists etc are all great ideas and are gaining momentum. But we cannot force presentation of CLIs. Can you imagine a divorce lawyer trying to contact their client who hasn’t told their abusive partner yet? Just one example of why that particular right to privacy is enshrined in law.

Also the iPhone feature is brilliant – perfect for in laws too

The telephone network is not a computer network and therefore any solutions for call blocking cannot be universally applied for all providers, thus making them expensive and unlikely to work effectively.

The UK needs to lead the way and modernise the telephony network to begin to solve the operational problems that we face, such as nuisance calls and telephone number routing issues.

This is a complex problem even when presented with a nice environment to develop solutions. Using technologies like SIP or other open standards allows for us to build software that can be very cost effectively deployed at the carrier level to begin to try and solve this type of problems.

To all those that oppose ISP porn filters on account of the fact that they block innocent traffic too, think again about call blocking. How can the software know if an unsolicited call is from a call centre or just a friend of a friend that was given your number to see if you wanted a new job?

Thanks all for your comments.

@Peter Farmer – I thought the BT charge was dependent on how far they had to carry the call, e.g. calculated from the interconnect to the exchange then plus 0.0137p for the exchange to the subscriber. I was also under the impression that a minimum charge applies. It’s a while since I looked at this so I accept things will have changed.

To add about the technical challenges of blocking, BT do already offer a service that cut our calls significantly. As a cost-cutting exercise we stopped paying for the service and the calls returned. Now I feel hostage!

Hi James

Indeed the total cost of the call is based on the actual conveyed distance and includes markups for each switching party in the process, however, the market for that sort of conveyance is so competitive (including internationally) and the vast majority of fixed originated calls terminate directly on the BT exchange, that for the volumes these diallers generate and the margins that are sustainable, it’s still a ridiculously small number divided by a large number of players.

I guess my point was that there isn’t really a financial moral hazard at the terminating end, especially considering the costs incurred in the adverse consequences of this number of calls per second hitting core networks etc; the EU and Ofcom have seen to this by the economic model used in calculating fixed and mobile termination rates.

The money is made at the originating end, in terms of the connectivity to the dialler in SIP channels and the rates levied for the calls – that’s where the moral hazard exists; matched by an equal incentive for the terminators to generate chargeable products to help their customers.

24 million households in the UK and about as many businesses again, give or take. Let’s call that 48m landlines for sake of argument. If you could charge them all just a penny a day for a blocking product, that’s £480k a day revenue – orders of magnitude more than the foregone termination revenue.

Which, having now done that maths, means I am getting my software development hat on pretty quick 🙂

Peter – how would a blocking product work? How to determine numbers to allow or block?

Only about 30m premises in the UK. Not had any nuisance calls recently, must be the weather.

I had Anonymous Caller Rejection from Virgin Media, which was (and is) cheaper than BT, but would much prefer the option of being able to filter out such calls without having to install a call blocker. I can appreciate that offices don’t want to get inundated with unwanted calls from people asking who called them, but seeing ‘WITHHELD’ is unpleasant – surely their PBXs could be configured with a generic number with a recorded announcement identifying the organisation?

My biggest bugbear is with overseas call centres, as up to now, BT has refused to display CLI from outside the UK, and is only now changing that, as it plans to enable its exchanges to do this by this autumn.

People elsewhere in Europe have been able to see my BT number as ‘0044 etc’ and return my calls., which are displayed as The irony is that BT claim this is for security reasons, but scammers spoofing Caller ID is making a mockery of that!

My experience when using Virgin Media was that international CLI would be compressed into a domestic UK eleven-digit format. When someone phoned from a Dutch or Australian number, the 0031 or 0061 prefix would be displayed as ’01’, making it look like a UK number , eg: 01206xxxxxx for a number in Amsterdam or 01407xxxxxx for a mobile number in Australia.

On the other hand, when I used VoIP services like Sipgate, and someone called me from Brussels, his number showed up as 00322xxxxxxx, so correct international format.

A blocking service can easily work on either the Presentation CLI or the Network CLI (though I need to think through the lawfulness of processing that for a product, because of various privacy statutes)….. in any event, wholly reliant on neither being abused.

If we had such a service how would we tell the difference between a call from a solar panel company sending Withheld, and someone we know sending Withheld?

Providing the appropriate standard is followed (ND1646 or something), then the Presentation CLI will be witheld at the request of the calling party, but the Network CLI is still intact – the use of this for blocking is something I need to get into as there are obvious privacy issues in processing it for this purpose as it is confidential information.

However, that can get corrupted, or substituted/spoofed if you know what you’re doing, so one key question is, how do yuou know it’s not a PPI Salesman pretending to be the mother in law, or your mother in law.

In both cases, safe to reject the call 😉

I got a call yesterday from someone in the Philippines conducting a survey, I’m not sure if having a UK CLI would have made any difference. However, I was expecting someone to call me from Portugal, so took it on the chance that it might be him. When I was in touch with him in 2001, his number would come up on Telewest Caller Display as 04282xxxxxx, despite the code for Portugal being 00351 (Spain is 0034, so having a ‘4’ has a bit more logic.

I use free geographical DIDs from and if I need to enter a phone number, that what I use. (They’ve run out of London ones, surprise, surprise, so it’s just as well I no longer live in the 020 area.) One advantage is that even if people prefix calls with ‘141’, their numbers are still displayed.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.