The ASAI is investigating "a handful" of specific complaints brought to its attention over the past month, but in a departure from normal procedure it is also looking at advertising and marketing standards across the entire highspeed internet industry.

The main area of concern for the independent regulator is contention ratios.

This is the ratio of total bandwidth available to be shared amongst broadband subscribers connected to the same local phoneline. The number of people sharing a line . . . up to 50 households in some cases . . . has a massive effect on the speeds enjoyed by each customer.

The ASAI feels this aspect of broadband subscription is not being made clear in marketing and advertising material.

"We're looking at the number of customers on a line and wider advertising issues, " said a spokeswoman. "Because the technology is so often dependent on individual circumstances, that does have an impact on what customers get. It's not really black and white but there is definitely an issue here, " she said.

The advertising body has contacted communications regulator Comreg and the National Consumer Agency to gain more information regarding the complaints it is currently investigating. These are understood to relate to the larger, national broadband operators rather than smaller regional providers.

The ASAI declined to comment on investigations under way.

Irish broadband operators advertise generally-available standard packages ranging from one megabit per second to 12Mbps. However research undertaken by Blacknight Solutions, which runs a free broadband speed testing service at www. irishisptest. com, has found a staggering range of speeds from a truly pedestrian 0.104Mbps download speed on a UTV connection, to a jaw-dropping 59Mbps link for UCD's high-speed link.

According to Blacknight managing director Michele Neylon, the average download speed in Ireland is 1.79Mbps based on 250,000 speed tests since spring 2006. Average upload speed . . . how fast data can be sent 'up' from a computer to the internet . . . is 0.6Mbps.

Results of a British broadband survey released by consumer magazine Which? last week found the average speed amongst a sample of 300 customers paying for 8Mb connections was 2.7Mbps.

The UK's Advertising Standards Agency (ASA) is currently investigating complaints while British communications regulator Ofcom is monitoring the situation.

Which? editor Malcolm Coles told reporters: "It is shocking that internet service providers can advertise everincreasing speeds that seem to bear little resemblance to what most people can achieve in reality."