Britain's internet speeds lag behind other countries including Taiwan and Latvia

The need to overhaul Britain's ailing broadband network was laid bare yesterday as research showed it is "not ready for tomorrow" and lags behind 20 countries including Taiwan and Latvia.

South Korea was named the most advanced in Cisco's global study into broadband by country. The UK was 25th with a service that just meets its citizens' current broadband needs. It fell from 15th last year, but while the service has improved, other countries' investment has leapfrogged it.

A spokeswoman for the Department for Business Innovation and Skills welcomed the report, saying it showed "considerable improvement in the UK".

This comes as the Government attempts to overhaul broadband infrastructure, offering access to every household in the country by 2012, as outlined in the "Digital Britain" report.

Cisco's research measured how many citizens a country's broadband infrastructure reached as well as the quality of service. The Republic of Ireland was in 16th, one place behind the US.

Charlie Ponsonby, the chief executive of broadband comparison company, said: "There is a clear pattern emerging, with Scandinavia, eastern Europe and the Asian 'tiger' economies having far better developed broadband infrastructures. This may not give them a competitive edge today, but it certainly will tomorrow."

Broadband reaches 71 per cent of British households with Cisco's "quality score" rated at 30.8 points. The quality of the network is calculated on download and upload speeds and latency. The UK's average speed is 4 Mbps, enough to watch the BBC's iPlayer but below the global average. South Korea has an average speed of 40 Mbps, covering 97 per cent of its population.

Britain relies on a DSL broadband infrastructure, which uses copper phone lines that can produce speeds of up to 24 Mbps. BT is rolling this out to 75 per cent of the population and plans to spend £1.5bn on fibre network by 2012.

Fibre networks allow much quicker speeds. Virgin Media offers 50 Mbps, allowing users to download movies in just a few minutes. It is also trialling a 100 Mbps service. Fibre covers 50 per cent of UK homes. "Digital Britain" hopes to bring that up to 65 per cent.

British broadband speed is on the threshold needed to deliver a consistent service for today's common use of the internet from social networking sites to streaming low-definition video and sharing files including photos and music, the report said.

Yet only nine countries have the infrastructure for the broadband quality needed for forthcoming services including high-definition internet television and high-quality video communications which "will become mainstream in the next three to five years" according to Cisco.

The research was carried out by a team of MBA students from the Saïd Business School at the University of Oxford and the University of Oviedo's Department of Applied Economics. The researchers used more than 24 million records from broadband speed tests around the world.

Not a single British city made the top 20 for broadband quality, a list that includes Sofia in Bulgaria, Riga in Latvia and Kosice, Slovakia, which have all benefit from recent investments in fibre.

Fernando Elizalde, an analyst at Gartner, said the report's findings were not a surprise. "There's not much competition and there's reliance on copper wires. The UK hadn't been convinced of the business case."

Leading the way: South Korea on the net

South Korea leads the world with the quality of its broadband infrastructure, overtaking last year's champion Japan. Its continuing investment in technology and broadband in particular saw a 73 per cent improvement in its quality score.

Cisco's report said the improvements to South Korea's network mean the country was already prepared for the forthcoming increase in high-definition television streaming and video communications. "This has been driven by continuous efforts by the government to strengthen the country's position as one of the world's information and communication technology leaders," the document said.

South Korea has invested heavily in technology over the past decade in an attempt to boost its global standing, with the liberalisation of the telecoms industry in the 1990s also boosting competition in the market. Just over 10 years ago, only one in 100 citizens had access to the internet. Now the figure is 97 per cent.

South Korea has average broadband speeds of 40Mbps and the government has committed to bringing universal broadband speeds of up to 1Gbps by 2012.

Britain has committed to universal broadband of a minimum of Mbps. The United Nations rates South Korea as the leader for internet opportunity. Super-fast broadband has a darker side as it is thought to have brought internet pirates flocking into South Korea.