/ Technology

Slow broadband? Your ISP could be to blame

Snail on top of computer mouse

Research out yesterday shows that almost a third of UK households are getting far below the national average broadband speed. It may be that your internet service provider is deliberately slowing it down. But why?

Just this morning I was trying to watch live BBC on iPlayer owing to a CBeebies clash with my six-year-old daughter.

I clicked play but, after watching the scroll wheel turn for a couple of minutes, a message popped up to say the programme wouldn’t play.

It could be a blip or it could very well be because my internet service provider (ISP) is managing my broadband traffic – or, to put that in plain English, slowing my connection down on purpose.

What is traffic management?

Traffic management (also referred to as broadband throttling) refers to a practice deployed by many ISPs to manage, or slow down, certain types of traffic across their network.

The ISPs claim traffic management ensures that everyone using their services gets a good quality service. BT says it manages traffic in order to:

‘Provide the best experience for all our customers by ensuring that non-time-critical peer-to-peer traffic does not impact on the performance of time-critical services such as video streaming.’

Is your broadband being throttled?

BT makes a compelling argument which is in-keeping with recommendations in the government’s Digital Britain report (PDF). However, one of the problems with traffic management is that it’s almost impossible to know if it’s happening, when it’s happening and more specifically if it’s happening to you at any given time.

In a bid to find out more, Which? Computing sent a questionnaire to leading ISPs to find out who’s managing network traffic and when. Of the 17 companies we contacted, 11 told us that they deploy some form of traffic management.

The type of traffic that’s managed, and when, varies from provider to provider. BT, for example, manages P2P traffic between 4pm and midnight weekdays and 9am to midnight at the weekend. O2 also told us that it manages P2P traffic, watching videos and streaming. When this traffic is managed the speed you get will depend on your package.

To further complicate things, not all customers are necessarily managed. Virgin Media, for example, says it only employs traffic management to around 5% of its customers.

Catch-22 for consumers and ISPs

Generally speaking, the times that ISPs are managing traffic marry up with the times we know most of you want to be online. A survey of 11,963 Which? members in December 2011 found that 77% of them were online weekdays between 4pm and 10pm – and at weekends 66% of people were online at those times.

The ISPs say they have to manage traffic at these times because the network is busy but it also means you’re more likely to have a disappointing experience, like mine today.

Does it matter? Yes. Well it matters to me. OK, I can catch up on my news fix at 10pm when my daughter’s in bed, but the fact is I’ve paid my TV licence, which entitles me to Live Stream TV. What gives my ISP the right to stop me doing that?

And traffic management is only going to matter more as time goes on and services such as LoveFilm and Netflix become more popular. If I’ve paid for internet access and paid extra to stream video then the least I can expect is a watchable service.

So what do you think? Is your ISP managing your traffic and do you notice a slower service at peak times? Should ISPs be more open about traffic management? Would you pay more not to have your network managed?

Alan says:
2 June 2015

Surely this is fraud?
What is the point of Ofcom if they can’t take action on this?
It seems part of modern life now that dishonourable business conduct by companies is the norm.
If we are not being cheated by ISPs, gas and water companies are trying to frighten us into unnecessary insurance cover for boilers and drains.

Brulzie says:
25 August 2015

Bye Bye Virgin media: For the past week now I have had constant disconnections and when I finally get through to VM, they try to tell me that it’s my fault. Not so, I have friends and family on VM, most live close by, and when my internet goes down, theirs does too….. what, they think we don’t communicate outside of internet !.

Final straw was this evening. I rang to say that I’d had 3 disconnections in the past 10 minutes, but they stated that there were no reported ongoing problems (at all across the board), not on their status page anyway. So I contacted a couple of friends, yes, theirs were down too. I got irate, I got angry. Why do they try to fob us off by intimating that it’s our fault. Wake up Virgin Media, your customers are voting with their feet.

Brulzie says:
8 September 2015

Hello Virgin media.

Well my problems are resolved, no more disconnections and a customer service rep that actually cared about what I complained about. 1 month free service, which is nice.
Strangely enough, after I said I was leaving and so were some of my friends, the problems cleared up in record time.

Sickov Anti-service says:
3 September 2015

Don’t bother moving to TalkTalk either. One may be able to ‘talk talk’ all they like, but the fibre broadband has been down for 5 days now.
The imbeciles trying to sound like Americans STILL are reading parrot fashion from the screen in front of them and when I explain my extreme technical skills and experience and that the service is down OUTSIDE my home, they still wasted 25 minutes of my time asking stupid questions such as ‘can you try another browser to see if that resolves the problem’…

And what did i get yesterday? A text stating they have fixed the problem( they haven’t)…but if it hasn’t, call us again – the call will take FIFTEEN MINUTES (another waste of my time and money).


Talk talk are innocent BT have the exchange , always puzzled me that an ISP is blamed for an issue when only Openreach (nothing to do with BT who are wnderfufull lol) can carry out repairs to an infrastucture they have failed to maintain. and the customer can’t complain to BT because they aren’t their customer. Ofcom do nowt


Ofcom are like a guard dog with dentures. I have a 40 Mb connection , done a speed test no other device connected and get 9 Mb wirelessly (fac) an absolute joke who works the exchanges = Openreach , which engineers install BB = Openreach , who controls other ISP’S installs = Openreach Who has received millions from the government = Openreach it’s maybe about time they actually delivered . Ofcom will do sod all to resolve the monopoly BT have to many backhanders at stake


Sorry Ian as an ex BT engineer but having many “run ins ” with BT over service I still have to come out and defend them. I have to remind you that it was the Government that forced this situation of separating BT and its external network service Big Business Insisted on it ,no ifs,buts, or maybe,s . In hard drawn up legal terms BT cant influence Open Reach any more than another private company and BT is a private company . IN regards to breaks in service -again you havent all the facts many telephone exchanges in the UK are LLU – meaning =UNBUNDLED -thats right PRIVATE telephone companies put their money and TECHNICAL GEAR into a BT exchange releasing them from relying on BT to administer their broadband and telephone lines , newspapers always attack BT but keep quiet about other telecom companies its always “bad BT ” well I hope this puts the record straight -bad connections on Talk -Talk -Vodaphone etc etc -DONT blame BT as these companies use their OWN equipment.

Dick Whittington says:
20 August 2016

Lolz! Speed testing on wireless? Fail! Connect by Ethernet to the router and see that jump up to at least 25Mbps! Also, use a reliable speedtest service like speedtest.btwholesale.com, not one that slows down your browser with a bloated webpage


Dick might be right – but if Ian’s ISP was only delivering 9Mps to his router, then wifi might not slow things down significantly.

At least, that is my experience with both PlusNet (~10Mps total) and Virgin (~20Mps) total, with either of those, I see no significant differences between wired and wifi speeds.

andrewchoras says:
27 October 2015

The major issue with BT as a wholeseller of Internet services is the dreadful delay when the Internet and/or telephone service fails. For example, for a very simple fault in the BT roadside cabinet, I have to report the service loss to the ISP who then contact BT, BT contact Open Reach, Open Reach contact their contractor or contractors and, three weeks later, two small, simple cables are reconnected inside the BT roadside cabinet. Compared to Virgin Media, and a major fault was resolved within three hours. Provided that you can tolerate the prolific junk mail from Virgin Media, and you have their fibre optic service available, you can step away from BT and their lingering public sector mentality.

SR says:
11 May 2016

Virgin BB slows down every evening from 70Mbs to less than 10Mbs. Not enough for video streaming on one tv set. Just as hopeless as tesco but now more expensive. Alright if you watch your tv in the morning

Steve Hollowood says:
2 October 2016

Plusnet must be amongst the worst ISP. Trying to get through to anyone to complain about slow broadband is a nightmare, and then it’s my fault for not living closer to the exchange and have aging copper wire connections. Then came the hard sell to buy fibre optic broadband! I think they are reducing speeds to sell this product. Or am I cynical?

Terry Toye says:
6 October 2016

My FTTC broadband with BT was tested at installation as being potential maximum of 34 MB download speed. (I’m 700 metres cable length from my Fibre cabinet).
Over the last year at least my download speed as checked on BT wholesale test, has been about 26.5MB.
A few months ago we had a large area, (our town and surrounding villages at least), mains outage for about 20mins. The next day I checked my download speed as I do every day around 12 to 1am and it was 33MB !!
It stayed at this speed for 10 yes ten days, never dropping to a lower speed. Then on the 11th day it was back down to 26.5MB – suddenly, no degradation, just a sudden change.
So, on the Sat 24th Sept 2016, from 12pm till 1pm, we had another wide mains power outage, (SSE told me about 9000 customers around Blandford Forum were affected ). AND, lo and behold, the same thing happened, my download speed jumped to 33MB and it has stayed at that rate till today, 6th Oct. That’s 12 days this time. Today back down to 26.5MB.
Please, somebody tell me why this happens. This is NOT a gradual dropping of speed because of line degradation.
There is no doubt in my mind, ( I’m a Comms Engineer), that it has been DELIBERATELY SWITCHED TO A LOWER SPEED. That’s A 20% reduction in my download speed and at these speeds is much more important than 75 to 60.
BT is behaving badly here, and I see from the forums that very few people get their problems resolved satisfactorily.
Mr. Grumpy from Dorset.

andrew hayes says:
10 May 2017

other people were not re-connected , enabling a larger total available bandwidth to be shared amongst users on same package’ or 33mbs is your default bandwidth and was later de-throttled to 26mbs

D Ford says:
2 March 2017

i would say we are definitely throttled. does that matter? Yes, a line test shows we can only get a maximum of 8 MB download and .34 for upload. (the joy of rural living). if we actually got that i would be happy but we dont. our contract with BT runs for 18 months and there is no realistic alternative where we live. i accept we chose to move here BUT, for the first six months speeds were good and reliableand perfectly acceptable even for MMOG. after this period however it went downhill fast and the lowest acceptable speed before BT will do anything has been reduced from 4 to 0.5 MB and the router drops connection continually keeping the noise attentuation at its highest. whereas we could both stream happily, this is no longer possible and forget gaming online. the real rub though is that BT have the gall to charge £18 per month for this sub-standard service and we are told fibre is far too expensive to install, despite the fact that the local windfarms have it for the turbine data.

the BT speedtest shows a result of 7.8 MB every single time its run but large downloads consistently show 2 MB as the max. its also very coincidental that if i don’t game online for a week or so the speeds go back up and a few days after playing the speed drops again, sadly the game is designed as P2P, THE most throttled service.


You could try a VPN D.Ford but even Virgin would eventually throttle you and an unlimited VPN costs and probably BT would do the same , if you had fibre I could guarantee that their unlimited package has no throttling even on P2P . As it looks like you only have copper due to your £18/month charge 8Mbps isn’t that bad I had only half that before I got fibre . You are right , if you are rural and BT is not upgrading your cabinet to FTTC then you are limited , even other iSP,s wont improve it greatly , have you thought of tethering ?


On about year 8 of hi cup problems, regardless of supplier. 1.5miles from exchange. 200m from super fast that arrived over 4 years ago. Drops in the evening, just enough to stop the i player i.e. 2meg or less the problem. Took many years to get engineer on site to look for intermittent evening fault. SURPRISE they find no day time fault and I get charged £180. 3 years later with co op trying we had 4 engineers on site for over a hour each time. They found faulty BT installed bits and checked for faults in day time. Problem still there. Also Welsh assy gov scheme to help those getting poor broadband would increase our 6meg unlimited per month bill to 12meg unlimited £340 month bill !
Whole problem is who to trust. Talk talk have equipment in BT exchange and sell via Co op to me. BT not talking to Talk talk. etc

Mark says:
26 January 2018

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