Internet services providers (ISP) have said they will not change the way they advertise and supply broadband sevrices, despite public support for the Crystal Clear Broadband Campaign.

We contacted the leading ISPs, including Orange, BT, Virgin and TalkTalk for comment.

The ISPs insisted that technical limitations stopped them being able to give consumers a true idea of what speeds could be delivered.

BT said it did make it clear to its customers what speeds could feasibly be achieved as it tested the lines.

"We do not believe we are pulling the wool over people’s eyes when it comes to broadband speeds. Like all other ISPs we do advertise an ‘up to’ broadband limit but what a specific customer can get is verbally outlined to them after we test their line.”

TalkTalk said: "We can't break the laws of physics - but what we are saying is that we will deliver the fastest service that is physically possible to homes, which could be up to 8Mbits/sec once we have unbundled customers' lines. Unlike our some of our competitors this won't be limited in any way.

“All our advertising does stress up to 8Mbits/sec for the technical] reasons; how far away the customer is located from their local telephone exchange, the time of day, how busy the internet is and the physical quality of the phone line (the copper wire). Our advertising is also approved by the ASA before it is issued and so we feel confident that we are adhering to our customer focused principles."

Virgin also said speed limits were out of its control. "Most broadband providers, including Virgin Media, advertise their top speed preceded by the words 'up to', indicating that the speed is the maximum achievable. It is important for consumers to understand that the speeds quoted by ISPs are based on all the technology working at optimum speeds."

However Andrew Ferguson, editor of thinkb roadband.com, was dismissive of these responses.

"The warnings are always in the small print and I doubt they warn people on sign-up over the phone etc

"Also the way some ISPs' sales staff are wording speed estimates is wrong. They are telling people they should get 6.5Mbps (or some other number) or faster so people feel more confident about the speeds. But this is the wrong way to use the estimator.

"Another issue to watch out for is people connecting at say say 8 Mbits/sec but
due to night time bursts of noise they have a much lower configured
throughput.

"This is something that probably affects a fair percentage of people and ISPs should make a resolution to find out and fix or make line less vulnerable to the bursts
of noise," he pointed out.

The one lone voice was . Mark Lang, the ISP's head of Eclipse Internet's warmly welcomed the campaign and its goals.

"The industry does need to be clearer on what speeds consumers can get and we do think Ofcom has a role to play in ensuring there is a standard test that consumers can rely on so they know what speeds they will get. There are huge variables that need to be taken into consideration such as contention ratios and technical limitations, but currently the explanations given to consumers can be misleading," he said.