BT Chooses Technology from Tatara Systems for Voice-Over-WLAN Trial.

NEW ORLEANS -- Tatara SIM Authentication Solution Enables Users to Switch Seamlessly Between GSM and WLAN Networks for Voice Calls

Tatara Systems Inc., a developer of converged mobile service solutions for communications service providers, today announced that its SIM Authentication technology through its Tatara Mobile Services Convergence Platform has been selected by British Telecom to form part of a ground-breaking voice-over-WLAN trial in the United Kingdom.

The trial aims to test the technological viability of enabling business users and private individuals to switch automatically between WLAN and GSM networks for voice calls.

Trial participants will be issued with HP iPAQ 6340 personal digital assistant (PDA) devices, enabled for WLAN and GSM voice connectivity. Initially the trial restricts Wi-Fi access to Adastral Park only but ultimately users will be able to make voice calls over WLAN networks at the office, at home, or at a public hotspot. When out of range of a WLAN network, the user will make voice calls over the standard GSM network.

The Tatara Subscriber Gateway and the Tatara Service Manager Software Developers Kit (SDK), elements of the Tatara Mobile Services Convergence Platform, form a key part of the technology infrastructure that BT is deploying to enable the trial. The Tatara Subscriber Gateway, already installed at BT's Adastral Park R&D labs at Martlesham Heath, UK, enables trial participants to automatically identify themselves securely to both WLAN and GSM networks through a single subscriber identity module (SIM) card installed within the iPaq. The connection between the PDA and the Tatara Subscriber Gateway is enabled using Tatara's SDK, which is installed on the iPaq device.

Tatara's Mobile Services Convergence Platform helps give BT the ability to offer a converged voice service with a seamlessly handoff from BT's partner GSM network to WLAN networks with the same high level of real-time control on WLAN networks as they have on their GSM network. For the SIM authentication portion of the trial, the Tatara Mobile Services Convergence Platform uses a unique two-stage authentication process for secure EAP-SIM authentication over both 802.1x and HTTP-based WLAN networks.

In addition, the Tatara product provides a strong level of customer care, including network diagnostics, performance monitoring, and billing system mediation. These features ensure high network availability and correct billing -- using a single bill -- for the services used.

The market will start to see considerable uptake of voice-over-WLAN in 2007, according to industry analyst firm Meta Group. Tatara believes that services will begin to roll-out in earnest in early 2006, and users will be attracted by the ability to make free or low-cost calls over an IP network while on the move.

"Initial uptake will be among businesses keen to reduce their communications costs," said Steve Nicolle, chief executive officer of Tatara Systems. "But the proliferation of public WLAN hotspots and home wireless networks, combined with the emergence of dual-mode (WLAN and GSM) handsets, is likely to spur uptake among consumers as well."

Tatara was the first company to provide SIM-based WLAN authentication in the real world. It demonstrated end-to-end authentication of a SIM user on a WLAN network in a project conducted with VeriSign and a regional GSM operator in the United States in March 2004. "Tatara's track record of innovation in this area made it the clear choice to provide the user authentication portion of this exciting new technology trial," said Mike Carr, Director Research and Venturing, BT Group.

The trial infrastructure is already in place at BT's Adastral Park research facilities in Martlesham Heath, UK. The trial is scheduled to begin in April 2005.

About BT

BT is one of the world's leading providers of communications solutions serving customers in Europe, the Americas and Asia Pacific. Its principal activities include IT and networking services, local, national and international telecommunications services, and higher-value broadband and internet products and services.

BT consists principally of three lines of business:

--BT Retail, providing a comprehensive range of communications and related services to more than 20m UK consumers and businesses.

--BT Wholesale, providing network services and solutions within the UK to more than 600 fixed and mobile operators and service providers including the provision of broadband and private circuits.

--BT Global Services, providing IT and networking services to meet the needs of multi-site organisations globally. BT Global Services operates in more than 130 countries and also offers international carrier services.

In the year ended 31 March 2004, BT Group's turnover was GBP 18,519 million with profit before goodwill amortisation, exceptional items and taxation of GBP 2,013 million.

BT Group plc is listed on stock exchanges in London and New York. British Telecommunications plc (BT) is a wholly-owned subsidiary of BT Group and encompasses virtually all businesses and assets of the BT Group.

For more information, visit www.bt.com/aboutbt.

About Tatara Systems

Tatara invents, develops, and deploys solutions for communication service providers allowing them to offer converged mobile services to their subscribers. Tatara's Mobile Services Convergence Platform gives service providers the ability to offer a rich and consistent set of converged mobile broadband services over multiple network technologies, including WLAN, WAN/3G, Wireless Broadband, and Wired, and with the same high level of real-time control on roamed networks as they have on networks they own. Based in Acton, Mass., Tatara Systems is a privately held company backed by the leading communications investment firms Highland Capital Partners and North Bridge Venture Partners. For more information, visit www.tatarasystems.com.