The finding comes from one of the most sophisticated and thorough research programmes undertaken into the real broadband speeds experienced by UK consumers. Over a 30 day period approximately 7,000 tests were run through monitoring units connected to around 1,500 homes' broadband routers, resulting in over 10 million separate tests of a range of suppliers' services.
The research was conducted in association with broadband performance specialists SamKnows and market research company GfK Ltd.
3.6Mbit/s is sufficient for many internet applications, including audio and standard definition video. However, the speeds achieved are significantly below advertised headline speeds.
Among consumers on the most popular 'up to 8Mbit/s' package (which over 60% of UK broadband consumers subscribe to), one in five subscribers receives an average speed of less than 2Mbit/s and on average the actual speed consumers receive is 45% of the advertised headline speed.
Ofcom took measures to address this concern last month by requiring all Internet Service Providers (ISPs) signing up to the Broadband Speeds Code of Practice to provide an accurate estimate of the maximum speed they can expect when signing up to a service.
The research shows how DSL (Digital Subscriber Line) broadband speeds depend in part on distance from the local BT exchange. Largely because of distance, consumers living in urban areas received speeds which were on average 15% faster than those in rural areas. Consumers in London received the fastest average speeds, with those in the north east of England, Wales and Scotland receiving on average the slowest speeds.
DSL and cable broadband speeds vary by time of day due to differing traffic levels on ISPs' networks. Across the UK, speeds were slowest between 5pm and 6pm on Sundays, when use of the internet is at its highest.
The research also found that most consumers surveyed are reasonably happy with their broadband service, with 9% expressing dissatisfaction overall. However, speed was the most commonly cited cause of dissatisfaction.
Although 93% of consumers were satisfied with their experience of web browsing, satisfaction rates were lower among users of applications which typically benefit from faster speeds or more consistent performance. For example, only two thirds (67%) of those who use their broadband connection to watch or download TV programmes were satisfied with the experience.
The research also revealed that, while 91% of consumers said that speed was an important consideration when signing up with their current broadband provider, 28% of them were unaware of the headline speed package they purchased.
Overall, dissatisfaction with broadband is higher for rural users (14%) than urban users (8%). At a regional level, consumers in the North East, Eastern and South West English regions are significantly more satisfied than users in East Midlands, Wales and Scotland.
CODE OF PRACTICE AND CONSUMER GUIDE
Ofcom has taken a number of steps to ensure that consumers get better information about broadband speeds. Since 5 December 2008, over 95 per cent of people choosing a broadband service have been covered by the Ofcom broadband speeds Code of Practice which requires ISPs to provide an accurate estimate of the maximum speed they can expect when signing up to a service.
Under the code, in addition to providing an accurate estimate of the maximum speeds consumers will be able to receive, ISPs must also explain to customers the factors which determine the actual broadband speeds they can receive and give guidance on how to improve speeds. In December 2008, Ofcom published a guide for consumers on the steps they can take if they are unhappy with their broadband speeds which can be found at:
http://www.ofcom.org.uk/advice/guides/bbspeeds.pdf
Ofcom's Chief Executive, Ed Richards said: "Ofcom's research is one of the most comprehensive assessments of consumers' broadband experiences to date. We want to see all Internet Service Providers meet the needs of their customers by clearly explaining what speeds they should expect and by ensuring that their networks meet consumers' increasing demand for higher speed broadband."
"We have already seen the first steps towards next generation super-fast broadband in the UK and we expect further developments this year. Following our work last year, Ofcom will publish the next steps for the regulatory framework early this year."