Mobile Industry Leaders Complete Joint Specification for 3GPP IMS based Push to talk over Cellular (PoC) Technology

Press release
Sep 10, 2003 13:00 (GMT +00:00)
Industry leaders Ericsson, Motorola (NYSE: MOT), Nokia and Siemens mobile announced today the completion of a jointly developed Push to talk over Cellular (PoC) specification based on the IP Multimedia Subsystem (IMS) as defined by 3GPP.  This specification is intended to reduce marketplace fragmentation and provide end users with an easy-to-use push to talk experience wherever they may travel in the world. It was completed to meet a tremendous market interest in push to talk and IMS.

The PoC specification leverages existing 3GPP, OMA, and IETF specifications making the service easy to integrate in operators' existing access and packet core network infrastructures. The PoC specification is a bundle of six specifications including: Requirements, Architecture, Signaling Flows, Group/List Management, and two User-plane specifications (Transport and GPRS).

Ericsson, Motorola, Nokia and Siemens Mobile formed this PoC "technology co-operation" to produce a joint, fast track technology proposal to provide mobile operators with the assurance of easy integration, global interoperability and a competitive handset environment in the mobile communications market. The companies have submitted this specification to the Open Mobile Alliance (OMA) standards body for review as a baseline to provide an access-independent and globally interoperable standard for PoC.
Additionally, the PoC Specification has gained support from other industry leaders such as AT&T Wireless Services (NYSE: AWE), Cingular, Sonim Technologies, and Sony Ericsson. The specifications are currently available at

"End-users want to be able to use any enabled handset on any available network without having to worry about if they work together. This is true for all mobile services and push to talk will be no different", said Torbjörn Nilsson, Senior Vice President, Marketing and Strategic Business Development at Ericsson. "The access independent, interoperable, global industry specification that the major vendors now have agreed on is an important step towards ensuring that the end-users will get this".

"We realize how important interoperability is for the successful adoption of push to talk in the marketplace," said Philip Gilchrist, Vice President of Global Standards, Technical Asset Management and Advanced Solutions Realizations. "By working with mobile operators and other mobile handset and infrastructure leaders, we will be able to provide a clear PoC standard and rapidly bring interoperable solutions to market."

"Push to talk offers a fast and convenient way for connecting people globally", said Paul Chellgren, Senior Vice President, Product Management and Business Development, Nokia Mobile Phones Americas.. "The common approach to this technology by key vendors will enable us to bring the traditional usage of a two-way radio to a completely new level and accelerate the take-off of this new service. There clearly is a lot of demand on the market for a standardized Push to talk solution."

"Siemens mobile is committed to open standards and we see encouraging potential in Push To Talk", said Rudi Lamprecht, Boardmember of Siemens AG. "We had positive feedback from different operators and with this joint effort we are confident to bring Push To Talk to a success."

"Customers want services they know are dependable, easy-to-use and affordable," said Rod Nelson, chief technology officer for AT&T Wireless.  "An open interoperable specification for an important IMS service like push-to-talk is a big advantage and will give customers a winning solution."

"Standards lead to services transparency in the eyes of the customer and that is the route to widespread adoption.  Just as we saw with the interoperability of SMS, the ability for one customer to interact with another, without regard to their service provider, will be key to the success of this service,"  said Bill Clift, CTO - Cingular Wireless.  "This is an important step in that direction".

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 Motorola
Motorola, Inc. (NYSE: MOT) is an international leader in providing integrated communications and embedded electronic solutions. Sales in 2002 were $26.7 billion. Motorola is a global corporate citizen dedicated to ethical business practices and pioneering important technologies that make things smarter and life better for people. These traditions are as important today as they were when the company was founded 75 years ago this year. For further information, please visit
MOTOROLA, the Stylized M Logo are registered in the US Patent & Trademark Office. All other product or service names are the property of their respective owners.  © Motorola, Inc,. 2003
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 mobile
The Siemens Information and Communication Mobile Group (Siemens mobile) offers a complete range of mobile solutions including mobile devices, infrastructure and applications. Devices include mobile 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 € 11 billion and employed approximately 28,600 people worldwide.
You can access further information about Siemens mobile on the Internet at
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Notes to editors
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.

Eva Sparr, Ericsson Corporate Communications
Phone: +46 8 719 57 50
External Relations, Ericsson Corporate Communications
Phone: +46 8 719 69 92

Sharen Santoski
Telephone: +1-847-312-0806

Communications Department, Nokia Networks
Tel. (Int.) + 358 (0) 7180 38198
Press Desk
Nokia Americas
+1 972 894 4573

Franz-Rudolf Borsch
Telephone: +49-89-722-56642