The UK Advertising Standards Authority (ASA) is thought to be calling for a review of how broadband providers use contentious terms such as 'unlimited' when marketing download limits.

Currently the term is used to mean that the broadband company imposes no formal limit on downloading but reserves the right to limit a customer deemed to be breaching a 'fair usage' policy. What this means varies from provider to provider, which has sparked complaints to the ASA.

Especially contentious are mobile broadband operators. Only last week, O2 announced that it would be introducing a formal cap on its 'unlimited' mobile data service.

The ASA now intends consulting with the British Code of Advertising Practice (BCAP)and Committee of Advertising Practice (CAP), both bodies with the power to frame regulation, to see whether an all-encompassing definition is needed.

"It's important that we look at this on a broader policy level with service providers, other regulators and consumer groups, rather than relying on individual ASA rulings that focus on a particular service on one platform," the ASA's communications and policy manager, Lynsay Taffe, told New Media Age.

The likely outcome is that the word 'unlimited' will be banned unless a service is intended to have no data limit or shaping to enforce that by the back door. The small number of users who do manage to churn through hundreds of gigabytes of data each month will simply have to pay more on high-use tariffs with stated limits and charges.

The fundamental problem is that internet innovation is driving demand for online data faster than it can economically be serviced by providers, which creates the need for demand management through pricing, prioritisation or data caps.

"If it is not cost or a hard cap, then either traffic shaping or congestion will act as the control. Even the mobile network operators are finally accepting that unlimited data bundles are not viable as mobile phones become more interactive devices that consume a lot of data," said Sebastien Lahtinen of comparison site, thinkbroadband.com.

The likely outcome is that the word 'unlimited' will be banned unless a service is intended to have no data limit or shaping to enforce that by the back door. The small number of users who do manage to churn through hundreds of gigabytes of data each month will simply have to pay more on high-use tariffs with stated limits and charges.