Public Wi-Fi operators from around the world are meeting in London this week to discuss the next steps in the expansion of the Wireless Broadband Alliance. The 17 members of the alliance, who include BT Openzone and T-Mobile, plan to allow their subscribers to roam across all the member networks.

The WBA started in Asia, before adding BT in the UK and T-Mobile in the US. It has now recruited T-Mobile in Austria, the Czech Republic, Germany and the Netherlands, plus Telecom Italia and more members in Asia.

WBA spokesman Kyong Yu says it has a standard logo for all its members to use, and also has technical and marketing working parties. Among its aims is a common authentication scheme for all the networks involved. So far, Openzone roaming is only live with Singapore's StarHub, although trials are underway with others.

The WBA does look like an attempt by the big telcos to seize as much of the business Wi-Fi roaming market as possible: all the members are telcos or mobile phone operators.

Steve Andrews, MD of BT's Retail, Products & Enterprises group, says that membership of the WBA will make it simpler for travellers, as it means one common brand to look for. However, he adds that BT Openzone's bilateral roaming agreements with the likes of Telia-Sonera will continue, so it is obviously not quite that simple yet.

Nor is it all that cheap. In addition to their Openzone subscription, customers roaming onto the Telia-Sonera network must pay 20p per minute of usage. WBA roaming charges have not yet been set but are likely to be similar, so if you were hoping to use a $40/month T-Mobile US unlimited usage subscription in place of BT's £85/month equivalent, you can forget it.

Andrews says BT will make Openzone access free for a week from 26 January to 1 February 2004, in order to boost usage. He claims BT now has 1700 hotspots; however, this includes 1300 sites belonging to The Cloud, which Openzone users can roam onto.

He adds that, as part of its Wireless Broadband Week, BT will spend £1 million on promoting public Wi-Fi: "We are going to show everyone in the UK what this is about - how widely available and simple it can be. We'll also reassure them about security."