Ofcom wants accurate estimates of maximum broadband speeds
The way broadband speeds are advertised is to be regulated under a voluntary code published by Ofcom.
It wants companies to publish accurate estimates of the maximum connection speeds people can expect before they buy broadband packages.
Some 32 internet providers, covering more than 90% of UK broadband customers, have agreed to the code.
The media regulator also says customer internet satisfaction has fallen in the past year.
Ofcom is also undertaking what it says is the UK's "most authoritative and comprehensive broadband speed survey" to identify broadband performance across the country and its relationship to advertised speeds.
There are several steps that fixed-line internet service providers (ISPs) - ones that use cables - are required to take under the voluntary code.
providing customers with an accurate estimate of the maximum speed that the line can support, whether in a shop, over the internet or on the phone
resolving technical issues to improve speed
offering customers the choice to move onto a lower speed package when estimates given are inaccurate
providing consumers with information on usage limits
alerting customers when they have breached usage limits
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Ofcom's chief executive Ed Richards said: "Broadband is a thriving market in the UK. We want to encourage real clarity for consumers about the actual broadband speeds they can receive.
"This voluntary code is a significant step in this direction."
Anna Bradley, chair of Ofcom's Consumer Panel described the creation of the code as a "welcome move".
...as far as I can see, the code does nothing to stop ISPs labelling their products in the same "up to a zillion megs" way they always have.
"It addresses the concerns that we raised with Ofcom last year about the mismatch between the speeds that people think they are buying and what they actually get," she said in a statement.
Ms Bradley added that Ofcom must be "strict" in monitoring the code and said repeated breaches of it by net suppliers might signal the need for a mandatory Code of Practice.
The Internet Service Providers' Association (ISPA) said it supported the principle of the code and had helped to draw it up.
ISPA added that it would like the code to be extended to include mobile operators who offer wireless services to reduce confusion among consumers.
Ofcom has also previously reported that the geographical digital divide had been closed across the country, after its research found that homes in rural areas were more likely to have broadband than those in towns.
But a survey for BBC News suggested rural areas generally fared worse than towns, with telephone-line lengths and lack of access to cable being blamed.
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