Ericsson, Nokia and Siemens are jointly defining specifications for an open standard to speed the adoption of direct-call push to talk service over GPRS.  Push to talk is a cost-efficient, simple to use direct voice service for GPRS-based systems that has attracted the interest of leading operators.  The technology uses the capabilities of the IP Multimedia Subsystem (IMS) as specified by 3GPP for enabling IP connections between mobile phones.  Initial trials are expected to begin in the second half of 2003. 

The specifications created through this collaboration will be submitted to relevant industry bodies in order to create a standard that will avoid fragmentation and establish a unified push to talk over GPRS market with the same economies of scale that made GSM a global success.  The interoperable technology resulting from this work will allow mobile phones and networks to be used for push to talk communication using a variety of radio access networks. 

Ericsson, Nokia and Siemens are also inviting mobile network operators and other manufacturers to join them in creating an open, multi-vendor market for push to talk in the GSM evolution path (GSM/GPRS/EDGE/WCDMA) by developing products and services based on the open standard they are defining. 

"AT&T Wireless supports this joint initiative.  Our goal is to connect our customers to the people and information they care most about," said Rod Nelson, CTO of AT&T Wireless, "This new service, which will open to a broad audience, is another way to connect and is an example of how the scale and flexibility of GSM/GPRS/EDGE leads to new and cost effective services."

Cingular Wireless is in support of this cooperation and is evaluating push to talk technology for its customers. "We are always looking for new service offerings like push to talk, that allow our customers to quickly and simply connect to others" said Mike Dobbs, Vice President of Product Management at Cingular. "The standards-based approach taken by these manufacturers will allow carriers to ultimately deliver this service to the largest market in the most efficient and effective way."

"This collaboration will ensure that push to talk builds on the future proofed and standardized third generation core network IMS," says Dr. Jan Uddenfeldt, Senior Vice President Technology, Ericsson. "It will only have to be integrated once and is easily maintained, which brings great cost benefits to the operators. It demonstrates the importance of open standards for which Ericsson has always been a strong proponent."

"Push to talk provides cellular operators with a completely new means of connecting people," said Dr. J.T. Bergqvist, Executive Vice President, Nokia.  "It is an attractive option for instant voice communication, complementing present dialed voices services.  Push to talk's immediate type of communications can reach individuals or groups, and it can also be used to enable direct voice communication with other IMS-based services, such as interactive gaming.  GPRS and 3G mobile network operators, having more than 800 million customers today, can easily implement push to talk capability with a low level of additional investment to their existing networks." 

"Push to talk services - to be deployed on existing GPRS and future 3G networks -- will provide great value to both business users and consumers, and thus will help operators generate additional revenues," reinforces Harry Strasser, CTO & Senior Vice President, End-to-End Solutions, Siemens Information and Communication Mobile.  "These applications will enable operators to differentiate themselves from other players in the increasingly competitive landscape of mobile multimedia services.  The IMS will provide the IP-based control and will especially enable operators to leverage some of their key strengths -- for example, location information and presence -- to provide end-users with a truly new customer experience." 

Notes to editors
Push to talk:
Push to talk service is a two-way form of communications that allows users to engage in immediate communication with one or more receivers, similar to Walkie Talkie -- simply by pushing a button on their handsets.  Users receiving the transmission hear the sender's voice automatically without having to answer the call.  Business users like the fleet management communication between taxi drivers and their dispatcher is one concrete example of such a use case. Consumers benefit from push to talk service in coordinating recreational and social activities (for example, families or friends separated in a large ski resort or amusement park) representing a huge market potential for the services. Previous implementations of push to talk service in cellular networks have been based on proprietary technology and on a limited scale.  By bringing this functionality to GSM, the world's most successful wireless technology with over 800 million users in more than 190 countries, Ericsson, Nokia and Siemens are helping to open the market and fuel push to talk services with a truly global reach. 

IP Multimedia System (IMS) is a technology standardized by 3GPP.  It is a key development of the mobile communication into IP technologies. It adds the ability to deliver integrated voice and data services over the IP-based packet switched network.  IMS adds two fundamental capabilities on top of the packet switched domain; firstly the ability to find a person via SIP to initiate a session, and secondly the ability to integrate new revenue generating services, such as push to talk.  IMS offers a development environment that is well aligned with mainstream IP technology, thereby lowering the threshold for 3rd party application developers.  By introducing IMS and its services delivery capability, a step towards a common service delivery environment is taken. Instead of providing a complete service delivery infrastructure per service, a common infrastructure can be used, facilitating a reduced time to revenue and reduced cost (OPEX and CAPEX) for new service introduction.

About AT&T Wireless Systems
AT&T Wireless (NYSE: AWE) is the second-largest wireless carrier, based on revenues, in the United States. With 20.859 million subscribers, and full-year 2002 revenues exceeding $15.6 billion, AT&T Wireless will continue delivering advanced high-quality mobile wireless communications services, voice or data, to businesses and consumers, in the U.S. and internationally. For more information, please visit us at <>.

About Cingular Wireless
Cingular Wireless, a joint venture between SBC Communications (NYSE - SBC) and BellSouth (NYSE - BLS), serves more than 22 million voice and data customers across the United States. A leader in mobile voice and data communications, Cingular is the only U.S. wireless carrier to offer Rollover, the wireless plan that lets customers keep their unused monthly minutes. Cingular provides cellular/PCS service in 43 of the top 50 markets nationwide, and provides corporate e-mail and other advanced data services through its GPRS and Mobitex packet data networks. Cingular offers Mobitex service in 99 of the top 100 markets nationwide. Details of the company are available at .

About Ericsson
Ericsson is shaping the future of Mobile and Broadband Internet communications through its continuous technology leadership. Providing innovative solutions in more than 140 countries, Ericsson is helping to create the most powerful communication companies in the world.

About Nokia
Nokia is the world leader in mobile communications. Backed by its experience, innovation, user-friendliness and secure solutions, the company has become the leading supplier of mobile phones and a leading supplier of mobile, fixed broadband and IP networks. By adding mobility to the Internet Nokia creates new opportunities for companies and further enriches the daily lives of people. Nokia is a broadly held company with listings on six major exchanges.

About Siemens
The Siemens Information and Communication Mobile Group (Siemens mobile) offers the complete range of mobile solutions including mobile devices, infrastructure and applications. Devices include mobile phones, fashion accessory phones, wireless modules, mobile organizers and cordless phones as well as products for wireless home networks. The infrastructure portfolio includes GSM, GPRS and 3G mobile network technologies from base stations and switching systems to intelligent networks, e.g. for prepaid services. Mobile Applications cover end-to-end solutions for Messaging, Location Based Services or Mobile Payment. For fiscal 2002 (September 30), Siemens mobile recorded sales of EUR 11 billion and employed approximately 28,600 people worldwide. You can access further information about Siemens mobile on the Internet at